Devices, systems, and methods for reshaping a heart valve anulus, including the use of a bridge implant having an adjustable bridge stop

ABSTRACT

Implants or systems of implants and methods apply a selected force vector or a selected combination of force vectors within or across the left atrium, which allow mitral valve leaflets to better coapt. The implants or systems of implants and methods make possible rapid deployment, facile endovascular delivery, and full intra-atrial adjustability and retrievability years after implant. The implants or systems of implants and methods also make use of strong fluoroscopic landmarks. The implants or systems of implants and methods make use of an adjustable implant and a fixed length implant. The implants or systems of implants and methods may also utilise an adjustable bridge stop to secure the implant, and the methods of implantation employ various tools.

RELATED APPLICATIONS

This application is a continuation of co-pending application Ser. No.11/255,663 filed 21 Oct. 2005, which is a continuation-in-part of Ser.No. 11/089,949, filed 25 Mar. 2005, and entitled “Devices, Systems, andMethods for Reshaping a Heart Valve Annulus, Including the Use of aBridge Implant” which is incorporated herein by reference.

Application Ser. No. 11/255,663 is also a continuation-in-part ofapplication Ser. No. 10/894,433, filed Jul. 19, 2004, and entitled“Devices, Systems, and Methods for Reshaping a Heart Valve Annulus,”which is incorporated herein by reference.

Application Ser. No. 11/255,663 is also is a continuation-in-part ofSer. No. 10/846,850, filed May 14, 2004, and entitled “Devices, Systems,and Methods for Reshaping a Heart Valve Annulus,” which is incorporatedherein by reference.

FIELD OF THE INVENTION

The invention is directed to devices, systems, and methods for improvingthe function of a heart valve, e.g., in the treatment of mitral valveregurgitation.

BACKGROUND OF THE INVENTION I. The Anatomy of a Healthy Heart

The heart (see FIG. 1) is slightly larger than a clenched fist. It is adouble (left and right side), self-adjusting muscular pump, the parts ofwhich work in unison to propel blood to all parts of the body. The rightside of the heart receives poorly oxygenated (“venous”) blood from thebody from the superior vena cava and inferior vena cava and pumps itthrough the pulmonary artery to the lungs for oxygenation. The left sidereceives well-oxygenation (“arterial”) blood from the lungs through thepulmonary veins and pumps it into the aorta for distribution to thebody.

The heart has four chambers, two on each side—the right and left atria,and the right and left ventricles. The atriums are the blood-receivingchambers, which pump blood into the ventricles. The ventricles are theblood-discharging chambers. A wall composed of fibrous and muscularparts, called the interatrial septum separates the right and leftatriums (see FIGS. 2 to 4). The fibrous interatrial septum is, comparedto the more friable muscle tissue of the heart, a more materially strongtissue structure in its own extent in the heart. An anatomic landmark onthe interatrial septum is an oval, thumbprint sized depression calledthe oval fossa, or fossa ovalis (shown in FIGS. 4 and 6), which is aremnant of the oval foramen and its valve in the fetus. It is free ofany vital structures such as valve structure, blood vessels andconduction pathways. Together with its inherent fibrous structure andsurrounding fibrous ridge which makes it identifiable by angiographictechniques, the fossa ovalis is the favored site for trans-septaldiagnostic and therapeutic procedures from the right into the leftheart. Before birth, oxygenated blood from the placenta was directedthrough the oval foramen into the left atrium, and after birth the ovalforamen closes.

The synchronous pumping actions of the left and right sides of the heartconstitute the cardiac cycle. The cycle begins with a period ofventricular relaxation, called ventricular diastole. The cycle ends witha period of ventricular contraction, called ventricular systole.

The heart has four valves (see FIGS. 2 and 3) that ensure that blooddoes not flow in the wrong direction during the cardiac cycle; that is,to ensure that the blood does not back flow from the ventricles into thecorresponding atria, or back flow from the arteries into thecorresponding ventricles. The valve between the left atrium and the leftventricle is the mitral valve. The valve between the right atrium andthe right ventricle is the tricuspid valve. The pulmonary valve is atthe opening of the pulmonary artery. The aortic valve is at the openingof the aorta.

At the beginning of ventricular diastole (i.e., ventricular filling)(see FIG. 2), the aortic and pulmonary valves are closed to prevent backflow from the arteries into the ventricles. Shortly thereafter, thetricuspid and mitral valves open (as FIG. 2 shows), to allow flow fromthe atriums into the corresponding ventricles. Shortly after ventricularsystole (i.e., ventricular emptying) begins, the tricuspid and mitralvalves close (see FIG. 3)—to prevent back flow from the ventricles intothe corresponding atriums—and the aortic and pulmonary valves open—topermit discharge of blood into the arteries from the correspondingventricles.

The opening and closing of heart valves occur primarily as a result ofpressure differences. For example, the opening and closing of the mitralvalve occurs as a result of the pressure differences between the leftatrium and the left ventricle. During ventricular diastole, whenventricles are relaxed, the venous return of blood from the pulmonaryveins into the left atrium causes the pressure in the atrium to exceedthat in the ventricle. As a result, the mitral valve opens, allowingblood to enter the ventricle. As the ventricle contracts duringventricular systole, the intraventricular pressure rises above thepressure in the atrium and pushes the mitral valve shut.

The mitral and tricuspid valves are defined by fibrous rings ofcollagen, each called an annulus, which forms a part of the fibrousskeleton of the heart. The annulus provides attachments for the twocusps or leaflets of the mitral valve (called the anterior and posteriorcusps) and the three cusps or leaflets of the tricuspid valve. Theleaflets receive chordae tendineae from more than one papillary muscle.In a healthy heart, these muscles and their tendinous chords support themitral and tricuspid valves, allowing the leaflets to resist the highpressure developed during contractions (pumping) of the left and rightventricles. FIGS. 5 and 6 show the chordae tendineae and papillarymuscles in the left ventricle that support the mitral valve.

As FIGS. 2 and 3 show, the anterior (A) portion of the mitral valveannulus is intimate with the non-coronary leaflet of the aortic valve.As FIGS. 2 and 3 also show, the mitral valve annulus is also near othercritical heart structures, such as the circumflex branch of the leftcoronary artery (which supplies the left atrium, a variable amount ofthe left ventricle, and in many people the SA node) and the AV node(which, with the SA node, coordinates the cardiac cycle).

Also in the vicinity of the posterior (F) mitral valve annulus is thecoronary sinus and its tributaries. These vessels drain the areas of theheart suppled by the left coronary artery. The coronary sinus and itstributaries receive approximately 85% of coronary venous blood. Thecoronary sinus empties into the posterior of the right atrium, anteriorand inferior to the fossa ovalis (see FIG. 4). A tributary of thecoronary sinus is called the great cardiac vein, which courses parallelto the majority of the posterior mitral valve annulus, and is superiorto the posterior mitral valve annulus by an average distance of about9.64+/−3.15 millimeters (Yamanouchi, Y, Pacing and ClinicalElectophysiology 21(11):2522-6; 1998).

II. Characteristics and Causes of Mitral Valve Dysfunction

When the left ventricle contracts after filling with blood from the leftatrium, the walls of the ventricle move inward and release some of thetension from the papillary muscle and chords. The blood pushed upagainst the under-surface of the mitral leaflets causes them to risetoward the annulus plane of the mitral valve. As they progress towardthe annulus, the leading edges of the anterior and posterior leafletcome together forming a seal and closing the valve. In the healthyheart, leaflet coaptation occurs near the plane of the mitral annulus.The blood continues to be pressurized in the left ventricle until it isejected into the aorta. Contraction of the papillary muscles issimultaneous with the contraction of the ventricle and serves to keephealthy valve leaflets tightly shut at peak contraction pressuresexerted by the ventricle.

In a healthy heart (see FIGS. 7 and 8), the dimensions of the mitralvalve annulus create an anatomic shape and tension such that theleaflets coapt, forming a tight junction, at peak contraction pressures.Where the leaflets coapt at the opposing medial (CM) and lateral (CL)sides of the annulus are called the leaflet commissures.

Valve malfunction can result from the chordae tendineae (the chords)becoming stretched, and in some cases tearing. When a chord tears, theresult is a leaflet that flails. Also, a normally structured valve maynot function properly because of an enlargement of or shape change inthe valve annulus. This condition is referred to as a dilation of theannulus and generally results from heart muscle failure. In addition,the valve may be defective at birth or because of an acquired disease.

Regardless of the cause (see FIG. 9), mitral valve dysfunction can occurwhen the leaflets do not coapt at peak contraction pressures. As FIG. 9shows, the coaptation line of the two leaflets is not tight atventricular systole. As a result, an undesired back flow of blood fromthe left ventricle into the left atrium can occur.

Mitral regurgitation is a condition where, during contraction of theleft ventricle, the mitral valve allows blood to flow backwards from theleft ventricle into the left atrium. This has two importantconsequences.

First, blood flowing back into the atrium may cause high atrial pressureand reduce the flow of blood into the left atrium from the lungs. Asblood backs up into the pulmonary system, fluid leaks into the lungs andcauses pulmonary edema.

Second, the blood volume going to the atrium reduces volume of bloodgoing forward into the aorta causing low cardiac output. Excess blood inthe atrium over-fills the ventricle during each cardiac cycle and causesvolume overload in the left ventricle.

Mitral regurgitation is measured on a numeric Grade scale of 1+ to 4+ byeither contrast ventriculography or by echocardiographic Dopplerassessment. Grade 1+ is trivial regurgitation and has little clinicalsignificance. Grade 2+ shows a jet of reversed flow going halfway backinto the left atrium. Grade 3 regurgitation shows filling of the leftatrium with reversed flow up to the pulmonary veins and a contrastinjection that clears in three heart beats or less. Grade 4regurgitation has flow reversal into the pulmonary veins and a contrastinjection that does not clear from the atrium in three or fewer heartbeats.

Mitral regurgitation is categorized into two main types, (i) organic orstructural and (ii) functional. Organic mitral regurgitation resultsfrom a structurally abnormal valve component that causes a valve leafletto leak during systole. Functional mitral regurgitation results fromannulus dilation due to primary congestive heart failure, which isitself generally surgically untreatable, and not due to a cause likesevere irreversible ischemic or primary valvular heart disease.

Organic mitral regurgitation is seen when a disruption of the sealoccurs at the free leading edge of the leaflet due to a ruptured chordor papillary muscle making the leaflet flail; or if the leaflet tissueis redundant, the valves may prolapse the level at which coaptationoccurs higher into the atrium with further prolapse opening the valvehigher in the atrium during ventricular systole.

Functional mitral regurgitation occurs as a result of dilation of heartand mitral annulus secondary to heart failure, most often as a result ofcoronary artery disease or idiopathic dilated cardiomyopathy. Comparinga healthy annulus in FIG. 7 to an unhealthy annulus in FIG. 9, theunhealthy annulus is dilated and, in particular, theanterior-to-posterior distance along the minor axis (line P-A) isincreased. As a result, the shape and tension defined by the annulusbecomes less oval (see FIG. 7) and more round (see FIG. 9). Thiscondition is called dilation. When the annulus is dilated, the shape andtension conducive for coaptation at peak contraction pressuresprogressively deteriorate.

The fibrous mitral annulus is attached to the anterior mitral leaflet inone-third of its circumference. The muscular mitral annulus constitutesthe remainder of the mitral annulus and is attached to by the posteriormitral leaflet. The anterior fibrous mitral annulus is intimate with thecentral fibrous body, the two ends of which are called the fibroustrigones. Just posterior to each fibrous trigone is the commissure ofwhich there are two, the anterior medial (CM) and the posterior lateralcommissure (CL). The commissure is where the anterior leaflet meets theposterior leaflet at the annulus.

As before described, the central fibrous body is also intimate with thenon-coronary leaflet of the aortic valve. The central fibrous body isfairly resistant to elongation during the process of mitral annulusdilation. It has been shown that the great majority of mitral annulusdilation occurs in the posterior two-thirds of the annulus known as themuscular annulus. One could deduce thereby that, as the annulus dilates,the percentage that is attached to the anterior mitral leafletdiminishes.

In functional mitral regurgitation, the dilated annulus causes theleaflets to separate at their coaptation points in all phases of thecardiac cycle. Onset of mitral regurgitation may be acute, or gradualand chronic in either organic or in functional mitral regurgitation.

In dilated cardiomyopathy of ischemic or of idiopathic origin, themitral annulus can dilate to the point of causing functional mitralregurgitation. It does so in approximately twenty-five percent ofpatients with congestive heart failure evaluated in the resting state.If subjected to exercise, echocardiography shows the incidence offunctional mitral regurgitation in these patients rises to over fiftypercent.

Functional mitral regurgitation is a significantly aggravating problemfor the dilated heart, as is reflected in the increased mortality ofthese patients compared to otherwise comparable patients withoutfunctional mitral regurgitation. One mechanism by which functionalmitral regurgitation aggravates the situation in these patients isthrough increased volume overload imposed upon the ventricle. Duedirectly to the leak, there is increased work the heart is required toperform in each cardiac cycle to eject blood antegrade through theaortic valve and retrograde through the mitral valve. The latter isreferred to as the regurgitant fraction of left ventricular ejection.This is added to the forward ejection fraction to yield the totalejection fraction. A normal heart has a forward ejection fraction ofabout 50 to 70 percent. With functional mitral regurgitation and dilatedcardiomyopathy, the total ejection fraction is typically less thanthirty percent. If the regurgitant fraction is half the total ejectionfraction in the latter group the forward ejection fraction can be as lowas fifteen percent.

III. Prior Treatment Modalities

In the treatment of mitral valve regurgitation, diuretics and/orvasodilators can be used to help reduce the amount of blood flowing backinto the left atrium. An intra-aortic balloon counterpulsation device isused if the condition is not stabilized with medications. For chronic oracute mitral valve regurgitation, surgery to repair or replace themitral valve is often necessary.

Currently, patient selection criteria for mitral valve surgery are veryselective. Possible patient selection criteria for mitral surgeryinclude: normal ventricular function, general good health, a predictedlifespan of greater than 3 to 5 years, NYHA Class III or IV symptoms,and at least Grade 3 regurgitation. Younger patients with less severesymptoms may be indicated for early surgery if mitral repair isanticipated. The most common surgical mitral repair procedure is fororganic mitral regurgitation due to a ruptured chord on the middlescallop of the posterior leaflet.

In conventional annuloplasty ring repair, the posterior mitral annulusis reduced along its circumference with sutures passed through asurgical annuloplasty sewing ring cuff. The goal of such a repair is tobring the posterior mitral leaflet forward toward to the anteriorleaflet to better allow coaptation.

Surgical edge-to-edge juncture repairs, which can be performedendovascularly, are also made, in which a mid valve leaflet to mid valveleaflet suture or clip is applied to keep these points of the leafletheld together throughout the cardiac cycle. Other efforts have developedan endovascular suture and a clip to grasp and bond the two mitralleaflets in the beating heart.

Grade 3+ or 4+ organic mitral regurgitation may be repaired with suchedge-to-edge technologies. This is because, in organic mitralregurgitation, the problem is not the annulus but in the central valvecomponents.

However, functional mitral regurgitation can persist at a high level,even after edge-to-edge repair, particularly in cases of high Grade 3+and 4+ functional mitral regurgitation. After surgery, the repaired.valve may progress to high rates of functional mitral regurgitation overtime.

In yet another emerging technology, the coronary sinus is mechanicallydeformed through endovascular means applied and contained to functionsolely within the coronary sinus.

It is reported that twenty-five percent of the six million Americans whowill have congestive heart failure will have functional mitralregurgitation to some degree. This constitutes the 1.5 million peoplewith functional mitral regurgitation. Of these, the idiopathic dilatedcardiomyopathy accounts for 600,000 people. Of the remaining 900,000people with ischemic disease, approximately half have functional mitralregurgitation due solely to dilated annulus.

By interrupting the cycle of progressive functional mitralregurgitation, it has been shown in surgical patients, that survival isincreased and in fact forward ejection fraction increases in manypatients. The problem with surgical therapy is the significant insult itimposes on these chronically ill patients with high morbidity andmortality rates associated with surgical repair.

The need remains for simple, cost-effective, and less invasive devices,systems, and methods for treating dysfunction of a heart valve, e.g., inthe treatment of organic and functional mitral valve regurgitation.

SUMMARY OF THE INVENTION

The invention provides devices, systems, and methods for reshaping aheart valve annulus, including the use of a bridge implant system havingan adjustable bridge stop.

One aspect of the invention provides devices, systems, and methodsincluding a bridge implant system having an adjustable bridge stop, thebridge stop comprising a bridge stop housing having a length and awidth, an aperture extending through the length of the bridge stophousing, the aperture sized and configured to allow a bridging elementto extend through at least a portion of the length of the aperture, andan adjustment mechanism coupled to the bridge stop housing to allowadjustment of a length of the bridging element. The adjustment mechanismmay include a catheter releasably coupled to the bridge stop to activatethe adjustment mechanism. In addition, the adjustment mechanism may belocated within the aperture within the bridge stop housing. Theadjustment mechanism may allow for only lengthening or only shorteningof the bridging element, or for both lengthening and shortening of thebridging element. The adjustment mechanism may also be sized andconfigured to allow for repeatable adjustment. The bridge stop may alsoinclude a relocation element, and the relocation element further mayinclude at least one radio-opaque marker.

In one embodiment, the bridge stop adjustment mechanism includes astatic state, with the bridge stop adjustment mechanism restraining thebridging element in the adjustment mechanism's static state, therebyrequiring a positive activation force necessary to allow the bridgingelement to be adjusted.

In an additional embodiment, the bridging element includes discrete stopbeads to allow the bridging element to be adjusted in discrete lengths.The bridging element may also include a toothed ribbon portion or aperforated ribbon portion or a threaded shaft portion extending throughat least a portion of the aperture in the bridge stop housing.

An additional aspect of the invention provides devices, systems, andmethods including a bridge implant system having an adjustable bridgestop, the bridge stop comprising a bridge stop housing, the housingcomprising an inner portion and an outer portion, the housing having alength and a width, an aperture extending through the length of thebridge stop housing, the aperture sized and configured to allow abridging element to extend through at least a portion of the length ofthe aperture, and an adjustment mechanism coupled to the bridge stophousing to allow adjustment of the bridging element. The adjustmentmechanism may comprise rotation of either the inner portion or the outerportion. In addition, the inner portion may be positioned completelywithin the outer portion, or the inner portion may extend partiallyoutside the outer portion.

Yet an additional aspect of the invention provides devices, systems, andmethods including a bridge implant system having an adjustable bridgestop, the bridge implant system comprising bridging element sized andconfigured to span a left atrium between a great cardiac vein and aninteratrial septum, a first bridge stop coupled to the bridging element,and a second bridge stop coupled to the bridging element, the secondbridge stop comprising, a bridge stop housing having a length and awidth, an aperture extending through the length of the bridge stophousing, the aperture sized and configured to allow a bridging elementto extend through at least a portion of the length of the aperture, andan adjustment mechanism coupled to the bridge stop housing to allowadjustment of the bridging element. The bridge stop housing may furthercomprise an inner portion and an outer portion, wherein the adjustmentmechanism may comprise rotation of either the inner portion or the outerportion to allow the bridging element to be lengthened or shortened.

Yet an additional aspect of the invention provides devices, systems, andmethods for adjusting a bridge stop of an implant system, the bridgestop comprising a bridge stop housing having a length and a width, anaperture extending through the length of the bridge stop housing, theaperture sized and configured to allow a bridging element to extendthrough at least a portion of the length of the aperture, and anadjustment mechanism coupled to the bridge stop housing to allowadjustment of a length of the bridging element. The adjustment mechanismmay include a catheter releasably coupled to the bridge stop to activatethe adjustment mechanism. In addition, the adjustment mechanism may belocated within the aperture within the bridge stop housing. Theadjustment mechanism may allow for only lengthening or only shorteningof the bridging element, or for both lengthening and shortening of thebridging element. The adjustment mechanism may also be sized andconfigured to allow for repeatable adjustment. The bridge stop may alsoinclude a relocation element, and the relocation element further mayinclude at least one radio-opaque marker.

Yet an additional aspect of the invention provides devices, systems, andmethods for adjusting a length of a bridging element of a bridge implantsystem within a chamber of a heart comprising providing a bridge stopcomprising a bridge stop housing having a length and a width, anaperture extending through the length of the bridge stop housing, theaperture sized and configured to allow a bridging element to extendthrough at least a portion of the length of the aperture, and anadjustment mechanism coupled to the bridge stop housing to allowadjustment of a length of the bridging element, and then operating theadjustment mechanism to lengthen or to shorten the bridging element.

In one aspect of the invention, the adjustment may be repeated until adesired length of the bridging element is achieved. Further, thebridging element may be allowed to settle for a predetermined timebefore repeating the operating the adjustment mechanism step. A cathetermay be coupled to the bridge stop adjustment mechanism, the catheterbeing used to operate the adjustment mechanism. Alternatively a cathetermay be coupled to the bridging element, the catheter being used tolengthen or shorten the bridging element.

In an additional embodiment, the devices, systems, and methods foradjusting a length of a bridging element of a bridge implant systemwithin a chamber of a heart may further comprise providing a catheter,the catheter including a proximal end and a distal end, the catheterhaving a first adjustment mechanism on its proximal end and a secondadjustment mechanism on its proximal end, coupling the first adjustmentmechanism to one of the posterior bridge stop and the anterior bridgestop, coupling the second adjustment mechanism to the bridging element,operating the first adjustment mechanism to allow adjustment of thebridging element, operating the second adjustment mechanism to lengthenor shorten the bridging element, and operating the first adjustmentmechanism again to re-secure the bridging element.

Other features and advantages of the invention shall be apparent basedupon the accompanying description, drawings, and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an anatomic anterior view of a human heart, with portionsbroken away and in section to view the interior heart chambers andadjacent structures.

FIG. 2 is an anatomic superior view of a section of the human heartshowing the tricuspid valve in the right atrium, the mitral valve in theleft atrium, and the aortic valve in between, with the tricuspid andmitral valves open and the aortic and pulmonary valves closed duringventricular diastole (ventricular filling) of the cardiac cycle.

FIG. 3 is an anatomic superior view of a section of the human heartshown in FIG. 2, with the tricuspid and mitral valves closed and theaortic and pulmonary valves opened during ventricular systole(ventricular emptying) of the cardiac cycle.

FIG. 4 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the interiorof the heart chambers and associated structures, such as the fossaovalis, coronary sinus, and the great cardiac vein.

FIG. 5 is an anatomic lateral view of a human heart with portions brokenaway and in section to show the interior of the left ventricle andassociated muscle and chord structures coupled to the mitral valve.

FIG. 6 is an anatomic lateral view of a human heart with portions brokenaway and in section to show the interior of the left ventricle and leftatrium and associated muscle and chord structures coupled to the mitralvalve.

FIG. 7 is a superior view of a healthy mitral valve, with the leafletsclosed and coapting at peak contraction pressures during ventricularsystole.

FIG. 8 is an anatomic superior view of a section of the human heart,with the normal mitral valve shown in FIG. 7 closed during ventricularsystole (ventricular emptying) of the cardiac cycle.

FIG. 9 is a superior view of a dysfunctional mitral valve, with theleaflets failing to coapt during peak contraction pressures duringventricular systole, leading to mitral regurgitation.

FIGS. 10A and 10B are anatomic anterior perspective views of the leftand right atriums, with portions broken away and in section to show thepresence of an implant system that includes an inter-atrial bridgingelement that spans the mitral valve annulus, with a posterior bridgestop positioned in the great cardiac vein and an anterior bridge stop,including a septal member, positioned on the inter-atrial septum, theinter-atrial bridging element extending in an essentially straight pathgenerally from a mid-region of the annulus to the inter-atrial septum.

FIG. 10C is an anatomic anterior perspective view of an alternativeembodiment of the implant system shown in FIGS. 10A and 10B, showing arelocation loop positioned at the anterior side of the implant forremoval or adjustment of the implant system days, months, or years afterthe initial procedure or adjustment.

FIG. 10D is an anatomic anterior perspective view of an alternativeembodiment of the implant system shown in FIGS. 10A and 10B, showing ananterior bridge stop without the addition of a septal member.

FIG. 11A is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system of the type shown in FIGS. 10A and 10B, with theanterior region of the implant extending through a pass-throughstructure, such as a septal member, in the inter-atrial septum andsituated in the superior vena cava.

FIG. 11B is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system of the type shown in FIGS. 10A and 10B, with theanterior region of the implant extending through a pass-throughstructure, such as a septal member, in the inter-atrial septum andsituated in the inferior vena cava.

FIG. 11C is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system of the type shown in FIGS. 10A to 10C, with theanterior region of the implant situated on the inter-atrial septum, aswell as in the superior vena cava and the inferior vena cava.

FIG. 12A is a side view of a septal member which may be used as part ofthe implant system of the type shown in FIGS. 10A and 10B.

FIG. 12B is a side view of a deployed septal member of the type shown inFIG. 21A, showing the member sandwiching portions of the septum throughan existing hole.

FIG. 12C is a perspective view of an alternative embodiment of theseptal member shown in FIG. 12A, showing a grommet or similar protectivedevice positioned at or near the center of the septal member.

FIG. 13 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes an inter-atrial bridging element thatspans the mitral valve annulus, with a posterior region situated in thegreat cardiac vein and an anterior region situated on the interatrialseptum, the inter-atrial bridging element extending in an essentiallystraight path generally from a lateral region of the annulus.

FIG. 14 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes an inter-atrial bridging element thatspans the mitral valve annulus, with a posterior region situated in thegreat cardiac vein and an anterior region situated on the interatrialseptum, the inter-atrial bridging element extending in an upwardlycurved or domed path generally from a lateral region of the annulus.

FIG. 15 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes an inter-atrial bridging element thatspans the mitral valve annulus, with a posterior region situated in thegreat cardiac vein and an anterior region situated on the interatrialseptum, the inter-atrial bridging element extending in a downwardlycurved path generally from a lateral region of the annulus.

FIG. 16 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes an inter-atrial bridging element thatspans the mitral valve annulus, with a posterior region situated in thegreat cardiac vein and an anterior region situated on the interatrialseptum, the inter-atrial bridging element extending in a curvilinearpath, bending around a trigone of the annulus generally from amid-region region of the annulus.

FIG. 17 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes an inter-atrial bridging element thatspans the mitral valve annulus, with a posterior region situated in thegreat cardiac vein and an anterior region situated on the interatrialseptum, the inter-atrial bridging element extending in a curvilinearpath, bending around a trigone of the annulus generally from amid-region region of the annulus, as well as elevating in an arch towardthe dome of the left atrium.

FIG. 18 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes an inter-atrial bridging element thatspans the mitral valve annulus, with a posterior region situated in thegreat cardiac vein and an anterior region situated on the interatrialseptum, the inter-atrial bridging element extending in a curvilinearpath, bending around a trigone of the annulus generally from amid-region region of the annulus, as well as dipping downward toward theplane of the valve.

FIG. 19 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes two inter-atrial bridging elementsthat span the mitral valve annulus, each with a posterior bridge stop inthe great cardiac vein and an anterior bridge stop on the inter-atrialseptum, the inter-atrial bridging elements both extending in generallystraight paths from different regions of the annulus.

FIG. 20 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes two inter-atrial bridging elementsthat span the mitral valve annulus, each with a posterior regionsituated in the great cardiac vein and an anterior region situated onthe interatrial septum, the inter-atrial bridging elements bothextending in generally curvilinear paths from adjacent regions of theannulus.

FIG. 21 is an anatomic anterior perspective view of the left and rightatriums, with portions broken away and in section to show the presenceof an implant system that includes three inter-atrial bridging elementsthat span the mitral valve annulus, each with a posterior regionsituated in the great cardiac vein and an anterior region situated onthe interatrial septum, two of the inter-atrial bridging elementsextending in generally straight paths from different regions of theannulus, and the third inter-atrial bridging elements extending in agenerally curvilinear path toward a trigone of the annulus.

FIGS. 22A and 22B are sectional views showing the ability of a bridgestop used in conjunction with the implant shown in FIGS. 10A to 10C tomove back and forth independent of the septal wall and inner wall of thegreat cardiac vein.

FIGS. 23 to 30 are anatomic views depicting representativecatheter-based devices and steps for implanting an implant system of thetype shown in FIGS. 10A to 10C.

FIG. 31 is an anatomic section view of the left atrium and associatedmitral valve structure, showing mitral dysfunction.

FIG. 32 is an anatomic superior view of a section of the human heart,showing the presence of an implant system of the type shown in FIGS. 10Aand 10B.

FIG. 33 is an anatomic section view of the implant system takengenerally along line 33-33 in FIG. 32, showing the presence of animplant system of the type shown in FIGS. 10A and 10B, and showingproper coaptation of the mitral valve leaflets.

FIGS. 34A to 34D are sectional views of a crimp tube for connecting aguide wire to a bridging element, and showing the variations in thecrimps used.

FIG. 35A is an anatomic partial view of a patient depicting accesspoints used for implantation of an implant system, and also showing aloop guide wire accessible to the exterior the body at two locations.

FIG. 35B is an anatomic view depicting a representative alternativecatheter-based device for implanting an implant system of the type shownin FIGS. 10A to 10C, and showing a bridging element being pulled throughthe vasculature structure by a loop guide wire.

FIG. 36A is an anatomic partial view of a patient showing a bridge stopconnected to a bridging element in preparation to be pulled and/orpushed through the vasculature structure and positioned within the greatcardiac vein.

FIG. 36B is an anatomic view depicting a representative alternativecatheter-based device for implanting a system of the type shown in FIGS.10A to 10C, and showing a bridge stop being positioned within the greatcardiac vein.

FIG. 37A is a perspective view of a catheter used in the implantation ofan implant system of the type shown in FIGS. 10A to 10C.

FIG. 37B is a partial sectional view showing a magnetic head of thecatheter as shown in FIG. 37A.

FIG. 38 is a perspective view of an additional catheter which may beused in the implantation of an implant system of the type shown in FIGS.10A to 10C.

FIG. 39 is a partial perspective view of the interaction between themagnetic head of the catheter shown in FIG. 37A and the magnetic head ofthe catheter shown in FIG. 38, showing a guide wire extending out of onemagnetic head and into the other magnetic head.

FIG. 40 is an anatomic partial perspective view of the magnetic catheterheads shown in FIG. 39, with one catheter shown in the left atrium andone catheter shown in the great cardiac vein.

FIG. 41 is a perspective view of an additional catheter which may beused in the implantation of an implant system of the type shown in FIGS.10A to 10C.

FIGS. 42A to 42C are partial perspective views of catheter tips whichmay be used with the catheter shown in FIG. 41.

FIG. 43A is a perspective view of a symmetrically shaped T-shaped bridgestop or member which may be used with the implant system of the typeshown in FIGS. 10A to 10C.

FIG. 43B is a perspective view of an alternative embodiment of theT-shaped bridge stop shown in FIG. 43A, showing the bridge stop beingasymmetric and having one limb shorter than the other.

FIG. 44A is a sectional view of a bridge stop which may be used with theimplant system of the type shown in FIGS. 10A to 10D, showing thebridging element adjustment feature in the closed position.

FIG. 44B is a sectional view of the bridge stop of the type shown inFIG. 14A, showing the bridging element adjustment feature in the openposition.

FIG. 45A is an anatomic partial perspective view of alternative magneticcatheter heads, with one catheter shown in the left atrium and onecatheter shown in the great cardiac vein, and showing a side to endconfiguration.

FIG. 45B is a partial sectional view of the alternative magneticcatheter heads of the type shown in FIG. 45A, showing a guide wirepiercing the wall of the great cardiac vein and left atrium andextending into the receiving catheter.

FIG. 45C is a partial perspective view of an alternative magnetic headof the type shown in FIG. 45B.

FIG. 46 is an anatomic partial perspective view of an additionalalternative embodiment for the magnetic catheter heads of the type shownin FIG. 45A, showing a side to side configuration.

FIG. 47 is a perspective view depicting an alternative embodiment of animplant system of the type shown in FIGS. 10A to 10D, showing the use abridge stop having a bridging element adjustment feature and alsoincluding a relocation loop.

FIG. 48 is a perspective view depicting an alternative embodiment of abridge stop having a bridging element adjustment feature, and showingthe bridging element adjustment feature in the open position.

FIG. 49 is a perspective view of the bridge stop shown in FIG. 48,showing the bridging element adjustment feature in the closed position.

FIGS. 50 through 52 are perspective views depicting alternativeembodiments of a bridge stop having a bridging element adjustmentfeature.

FIG. 53 is a sectional view of the bridge stop of the type shown in FIG.52, showing the bridging element adjustment feature in the closedposition and showing an adjustment catheter tip prior to coupling to thebridge stop for bridging element adjustment.

FIG. 54 is a sectional view of the bridge stop of the type shown in FIG.52, showing the bridging element adjustment feature in the open positionand showing the adjustment catheter tip coupled to the bridge stop forbridging element adjustment.

FIG. 55 is a top view depicting an alternative embodiment of a bridgestop having a bridging element adjustment feature.

FIG. 56 is a front view of the bridge stop shown in FIG. 55, showingretentive tabs within the bridge stop.

FIG. 57A is a sectional view of an alternative embodiment of a bridgelock having a bridging element adjustment feature, showing the bridgingelement in the locked position.

FIG. 57B is a perspective view looking into the bridge lock shown inFIG. 57A, showing the bridging element in the locked position.

FIG. 57C is a top view of the bridge lock shown in FIG. 57A, showing thebridging element in the locked position.

FIG. 58A is a sectional view of the bridge lock shown in FIG. 57A,showing the bridging element in the unlocked position.

FIG. 58B is a perspective view looking into the bridge lock shown inFIG. 57A, showing the bridging element in the unlocked position.

FIG. 58C is a top view of the bridge lock shown in FIG. 57A, showing thebridging element in the unlocked position.

FIGS. 59A through 60C are views of an alternative embodiment of thebridge lock shown in FIGS. 57A through 58C, and showing the alternativebridge lock having a rotating gate to provide a convenient mechanism toreset the bridge lock for adjustment.

FIG. 61 is a perspective view of an alternative embodiment of a bridgelock, the bridge lock having a bridging element adjustment feature, andshowing the bridging element adjustment feature in the open position.

FIG. 62 is a perspective view of the grooved component of the bridgelock shown in FIG. 61, and without the bridging element.

FIG. 63 is a section view of the grooved component of the bridge lockshown in FIG. 62, taken generally along line 63-63 of FIG. 62.

FIG. 64 is a perspective view of the snap component of the bridge lockshown in FIG. 61.

FIG. 65 is a front view of the bridge lock shown in FIG. 61, and showingthe bridging element adjustment feature in the unlocked position.

FIG. 66 is a front view of the bridge lock shown in FIG. 61, and showingthe bridging element adjustment feature in the locked position.

FIG. 67 is a perspective view of the bridge lock shown in. FIG. 61, andshowing an adjustment catheter having a pair of interacting cathetertips, the inner torquer tip being positioned on the toothed bridgingelement, with the outer torquer tip yet to be positioned on the bridgelock.

FIG. 68 is a perspective view of an alternative embodiment of the bridgelock shown in FIG. 61, the bridge lock having internal threads to allowfor threaded bridging element adjustment.

FIG. 69 is a perspective view of the threaded component of the bridgelock shown in FIG. 68.

FIG. 70 is a section view of the threaded component of the bridge lockshown in FIG. 69, taken generally along line 70-70 of FIG. 69.

FIG. 71 is a perspective view of the hub component of the bridge lockshown in FIG. 68.

FIG. 72 is an anatomic anterior perspective view of the left atrium anda portion of the right atrium, with portions broken away and in sectionto show the presence of an alternative implant system of the type shownin FIGS. 10A to 10D, the alternative implant system includes a multipleelement bridging element that spans the mitral valve annulus, and arelocation loop for removal or adjustment of the implant system.

FIG. 73 is an anatomic anterior perspective view of the left atrium anda portion of the right atrium, with portions broken away and in sectionto show the presence of an alternative implant system of the type shownin FIGS. 10A to 10D, the alternative implant system includes toothedribbon bridging element that spans the mitral valve annulus, and arelocation loop for removal or adjustment of the implant system.

FIGS. 74 and 75 are perspective views of alternative embodiments of aT-shaped bridge stop or member of the type shown in FIGS. 10A to 10D,showing T-shaped bridge stops having a bridge element adjustmentfeature.

FIGS. 76 and 77 are perspective views of alternative embodiments of aT-shaped bridge stop or member of the type shown in FIGS. 10A to 10D,showing T-shaped bridge stops having a bridging element tensioning onlyfeature.

FIG. 78 is a perspective view depicting an alternative embodiment of animplant system of the type shown in FIGS. 10A to 10D, showing the use aribbon bridging element.

FIG. 79 a perspective view depicting an alternative embodiment of animplant system of the type shown in FIGS. 10A to 10D, showing the use alooped bridging element.

FIG. 80A is a perspective view depicting an alternative embodiment of animplant system of the type shown in FIGS. 10A to 10D, showing the use abraided bridging element including curved ends on the anterior side andforming an anterior bridge stop.

FIG. 80B is a side view of a curved end of the braided bridging elementof FIG. 80A, showing the curved end in one state of curvature.

FIG. 80C is a side view of the curved end of the braided bridgingelement of FIG. 80A, showing the curved end in an additional state ofcurvature.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Although the disclosure hereof is detailed and exact to enable thoseskilled in the art to practice the invention, the physical embodimentsherein disclosed merely exemplify the invention which may be embodied inother specific structures. While the preferred embodiment has beendescribed, the details may be changed without departing from theinvention, which is defined by the claims.

I. Trans-Septal Implants for Direct Shortening of the Minor Axis of aHeart Valve Annulus

A. Implant Structure

FIGS. 10A to 10D show embodiments of an implant 10 that is sized andconfigured to extend across the left atrium in generally ananterior-to-posterior direction, spanning the mitral valve annulus. Theimplant 10 comprises a spanning region or bridging element 12 having aposterior bridge stop region 14 and an anterior bridge stop region 16.

The posterior bridge stop region 14 is sized and configured to allow thebridging element 12 to be placed in a region of atrial tissue above theposterior mitral valve annulus. This region is preferred, because itgenerally presents more tissue mass for obtaining purchase of theposterior bridge stop region 14 than in a tissue region at or adjacentto the posterior mitral annulus. Engagement of tissue at thissupra-annular location also may reduce risk of injury to the circumflexcoronary artery. In a small percentage of cases, the circumflex coronaryartery may pass over and medial to the great cardiac vein on the leftatrial aspect of the great cardiac vein, coming to lie between the greatcardiac vein and endocardium of the left atrium. However, since theforces in the posterior bridge stop region are directed upward andinward relative to the left atrium and not in a constricting manneralong the long axis of the great cardiac vein, the likelihood ofcircumflex artery compression is less compared to other technologies inthis field that do constrict the tissue of the great cardiac vein.Nevertheless, should a coronary angiography reveal circumflex arterystenosis, the symmetrically shaped posterior bridge stop may be replacedby an asymmetrically shaped bridge stop, such as where one limb of aT-shaped member is shorter than the other, thus avoiding compression ofthe crossing point of the circumflex artery. The asymmetric form mayalso be selected first based on a pre-placement angiogram.

An asymmetric posterior bridge stop may be utilized for other reasons aswell. The asymmetric posterior bridge stop may be selected where apatient is found to have a severely stenotic distal great cardiac vein,where the asymmetric bridge stop better serves to avoid obstruction ofthat vessel. In addition, an asymmetric bridge stop may be chosen forits use in selecting application of forces differentially andpreferentially on different points along the posterior mitral annulus tooptimize treatment, i.e., in cases of malformed or asymmetrical mitralvalves.

The anterior bridge stop region 16 is sized and configured to allow thebridging element 12 to be placed, upon passing into the right atriumthrough the septum, adjacent tissue in or near the right atrium. Forexample, as is shown in FIGS. 10A to 10D, the anterior bridge stopregion 16 may be adjacent or abutting a region of fibrous tissue in theinteratrial septum. As shown, the bridge stop site 16 is desirablysuperior to the anterior mitral annulus at about the same elevation orhigher than the elevation of the posterior bridge stop region 14. In theillustrated embodiment, the anterior bridge stop region 16 is adjacentto or near the inferior rim of the fossa ovalis. Alternatively, theanterior bridge stop region 16 can be located at a more superiorposition in the septum, e.g., at or near the superior rim of the fossaovalis. The anterior bridge stop region 16 can also be located in a moresuperior or inferior position in the septum, away from the fossa ovalis,provided that the bridge stop site does not harm the tissue region.

Alternatively, as can be seen in FIGS. 11A and 11B, the anterior bridgestop region 16, upon passing through the septum into the right atrium,may be positioned within or otherwise situated in the superior vena cava(SVC) or the inferior vena cava (IVC), instead of at the septum itself.

In use, the spanning region or bridging element 12 can be placed intotension between the two bridge stop regions 14 and 16. The implant 10thereby serves to apply a direct mechanical force generally in aposterior to anterior direction across the left atrium. The directmechanical force can serve to shorten the minor axis (line P-A in FIG.7) of the annulus. In doing so, the implant 10 can also reactivelyreshape the annulus along its major axis (line CM-CL in FIG. 7) and/orreactively reshape other surrounding anatomic structures. It should beappreciated, however, the presence of the implant 10 can serve tostabilize tissue adjacent the heart valve annulus, without affecting thelength of the minor or major axes.

It should also be appreciated that, when situated in other valvestructures, the axes affected may not be the “major” and “minor” axes,due to the surrounding anatomy. In addition, in order to be therapeutic,the implant 10 may only need to reshape the annulus during a portion ofthe heart cycle, such as during late diastole and early systole when theheart is most full of blood at the onset of ventricular systoliccontraction, when most of the mitral valve leakage occurs. For example,the implant 10 may be sized to restrict outward displacement of theannulus during late ventricular diastolic relaxation as the annulusdilates.

The mechanical force applied by the implant 10 across the left atriumcan restore to the heart valve annulus and leaflets a more normalanatomic shape and tension. The more normal anatomic shape and tensionare conducive to coaptation of the leaflets during late ventriculardiastole and early ventricular systole, which, in turn, reduces mitralregurgitation.

In its most basic form, the implant 10 is made from a biocompatiblemetallic or polymer material, or a metallic or polymer material that issuitably coated, impregnated, or otherwise treated with a material toimpart biocompatibility, or a combination of such materials. Thematerial is also desirably radio-opaque or incorporates radio-opaquefeatures to facilitate fluoroscopic visualization.

The implant 10 can be formed by bending, shaping, joining, machining,molding, or extrusion of a metallic or polymer wire form structure,which can have flexible or rigid, or inelastic or elastic mechanicalproperties, or combinations thereof. Alternatively, the implant 10 canbe formed from metallic or polymer thread-like or suture material.Materials from which the implant 10 can be formed include, but are notlimited to, stainless steel, Nitinol, titanium, silicone, plated metals,Elgilcy™, NP55, and NP57.

The implant 10 can take various shapes and have various cross-sectionalgeometries. The implant 10 can have, e.g., a generally curvilinear(i.e., round or oval) cross-section, or a generally rectilinear crosssection (i.e., Square or rectangular), or combinations thereof. Shapesthat promote laminar flow and therefore reduce hemolysis arecontemplated, with features such as smoother surfaces and longer andnarrower leading and trailing edges in the direction of blood flow.

B. The Posterior Bridge Stop Region

The posterior bridge stop region 14 is sized and configured to belocated within or at the left atrium at a supra-annular position, i.e.,positioned within or near the left atrium wall above the posteriormitral annulus.

In the illustrated embodiment, the posterior bridge stop region 14 isshown to be located generally at the level of the great cardiac vein,which travels adjacent to and parallel to the majority of the posteriormitral valve annulus. This tributary of the coronary sinus can provide astrong and reliable fluoroscopic landmark when a radio-opaque device isplaced within it or contrast dye is injected into it. As previouslydescribed, securing the bridging element 12 at this supra-annularlocation also lessens the risk of encroachment of and risk of injury tothe circumflex coronary artery compared to procedures applied to themitral annulus directly. Furthermore, the supra-annular position assuresno contact with the valve leaflets therefore allowing for coaptation andreduces the risk of mechanical damage.

The great cardiac vein also provides a site where relatively thin,non-fibrous atrial tissue can be readily augmented and consolidated. Toenhance hold or purchase of the posterior bridge stop region 14 in whatis essentially non-fibrous heart tissue, and to improve distribution ofthe forces applied by the implant 10, the posterior bridge stop region14 may include a posterior bridge stop 18 placed within the greatcardiac vein and abutting venous tissue. This makes possible thesecuring of the posterior bridge stop region 14 in a non-fibrous portionof the heart in a manner that can nevertheless sustain appreciable holdor purchase on that tissue for a substantial period of time, withoutdehiscence, expressed in a clinically relevant timeframe.

C. The Anterior Bridge Stop Region

The anterior bridge stop region 16 is sized and configured to allow thebridging element 12 to remain firmly in position adjacent or near thefibrous tissue and the surrounding tissues in the right atrium side ofthe atrial septum. The fibrous tissue in this region provides superiormechanical strength and integrity compared with muscle and can betterresist a device pulling through. The septum is the most fibrous tissuestructure in its own extent in the heart. Surgically handled, it isusually one of the only heart tissues into which sutures actually can beplaced and can be expected to hold without pledgets or deep grasps intomuscle tissue, where the latter are required.

As FIGS. 10A to 10D show, the anterior bridge stop region 16 passesthrough the septal wall at a supra-annular location above the plane ofthe anterior mitral valve annulus. The supra-annular distance on theanterior side can be generally at or above the supra-annular distance onthe posterior side. As before pointed out, the anterior bridge stopregion 16 is shown in FIGS. 10A to 10D at or near the inferior rim ofthe fossa ovalis, although other more inferior or more superior sitescan be used within or outside the fossa ovalis, taking into account theneed to prevent harm to the septal tissue and surrounding structures.

By locating the bridging element 12 at this supra-annular level withinthe right atrium, which is fully outside the left atrium and spaced wellabove the anterior mitral annulus, the implant 10 avoids theimpracticalities of endovascular attachment at or adjacent to theanterior mitral annulus, where there is just a very thin rim of annulustissue that is bounded anteriorly by the anterior leaflet, inferiorly bythe aortic outflow tract, and medially by the atrioventricular node ofthe conduction system. The anterior mitral annulus is where thenon-coronary leaflet of the aortic valve attaches to the mitral annulusthrough the central fibrous body. Anterior location of the implant 10 inthe supra-annular level within the right atrium (either in the septum orin a vena cava) avoids encroachment of and risk of injury to both theaortic valve and the AV node.

The purchase of the anterior bridge stop region 16 in fibrous septaltissue is desirably enhanced by a septal member 30 or an anterior bridgestop 20, or a combination of both. FIGS. 10A through 10C show theanterior bridge stop region including a septal member 30. FIG. 10D showsthe anterior bridge stop region without a septal member. The septalmember 30 may be an expandable device and also may be a commerciallyavailable device such as a septal occluder, e.g., Amplatzer® PFOOccluder (see FIGS. 12A and 12B). The septal member 30 preferablymechanically amplifies the hold or purchase of the anterior bridge stopregion 16 in the fibrous tissue site. The septal member 30 alsodesirably increases reliance, at least partly, on neighboring anatomicstructures of the septum to make firm the position of the implant 10. Inaddition, the septal member 30 may also serve to plug or occlude thesmall aperture that was created in the fossa ovalis or surrounding areaduring the implantation procedure.

Anticipating that pinpoint pulling forces will be applied by theanterior bridge stop region 16 to the septum, the forces acting on theseptal member 30 should be spread over a moderate area, without causingimpingement on valve, vessels or conduction tissues. With the pulling ortensioning forces being transmitted down to the annulus, shortening ofthe minor axis is achieved. A flexurally stiff septal member ispreferred because it will tend to cause less focal narrowing in thedirection of bridge element tension of the left atrium as tension on thebridging element is increased. The septal member 30 should also have alow profile configuration and highly washable surfaces to diminishthrombus formation for devices deployed inside the heart. The septalmember may also have a collapsed configuration and a deployedconfiguration. The septal member 30 may also include a hub 31 (see FIGS.12A and 12B) to allow attachment of the bridge stop 20. The septalmember 30 may also include a grommet or similar protective device 32positioned at or near the center of the septal member to allowunobstructed movement of the bridging element 12 through the septalmember, such as during adjustment of the bridging element 12 (see FIG.12C). The hub 31 may provide this feature as well.

A septal brace may also be used in combination with the septal member 30and anterior bridge stop 20 to distribute forces uniformly along theseptum (see FIG. 11C). Alternatively, devices in the IVC or the SVC canbe used as bridge stop sites (see FIGS. 11A and 11B), instead ofconfined to the septum.

Location of the posterior and anterior bridge stop regions 14 and 16having radio-opaque bridge locks and well demarcated fluoroscopiclandmarks respectively at the supra-annular tissue sites just described,not only provides freedom from key vital structure damage or localimpingement—e.g., to the circumflex artery, AV node, and the leftcoronary and non-coronary cusps of the aortic valve - - - but thesupra-annular focused sites are also not reliant on purchase betweentissue and direct tension-loaded penetrating/biting/holding tissueattachment mechanisms. Instead, physical structures and forcedistribution mechanisms such as stents, T-shaped members, and septalmembers can be used, which better accommodate the attachment or abutmentof mechanical levers and bridge locks, and through which potentialtissue tearing forces can be better distributed. Further, the bridgestop sites 14, 16 do not require the operator to use complex imaging.

Adjustment of implant position after or during implantation is alsofacilitated, free of these constraints. The bridge stop sites 14, 16also make possible full intra-atrial retrieval of the implant 10 byendovascularly snaring and then cutting the bridging element 12 ateither side of the left atrial wall, from which it emerges. As seen inFIG. 10C, relocation means, such as a hook or loop 24, may be providedto aid in re-docking to the bridge stop sites 14, 16 to allow for futureadjustment or for implant removal, for example. The relocation meansallows for adjustment or removal of the implant days, months, or evenyears after the initial procedure or after an adjustment.

D. Orientation of the Bridging Element

In the embodiments shown in FIGS. 10A to 10D, the implant 10 is shown tospan the left atrium beginning at a posterior point of focus superior tothe approximate mid-point of the mitral valve annulus, and proceeding inan anterior direction in a generally straight path directly to theregion of anterior focus in the septum. As shown in FIGS. 10A to 10D,the spanning region or bridging element 12 of the implant 10 may bepreformed or otherwise configured to extend in this essentially straightpath above the plane of the valve, without significant deviation inelevation toward or away from the plane of the annulus, other than asdictated by any difference in elevation between the posterior andanterior regions of placement.

Lateral or medial deviations and/or superior or inferior deviations inthis path can be imparted, if desired, to affect the nature anddirection of the force vector or vectors that the implant 10 applies. Itshould be appreciated that the spanning region or bridging element 12can be preformed or otherwise configured with various medial/lateraland/or inferior/superior deviations to achieve targeted annulus and/oratrial structure remodeling, which takes into account the particulartherapeutic needs and morphology of the patient. In addition, deviationsin the path of the bridging element may also be imparted in order toavoid the high velocity blood path within a heart chamber, such as theleft atrium.

For example, as shown in FIG. 13, the implant 10 is shown to span theleft atrium beginning at a posterior region that is closer to a lateraltrigone of the annulus (i.e., farther from the septum). Alternatively,the posterior region can be at a position that is closer to a medialtrigone of the annulus (i.e., closer to the septum). From either one ofthese posterior regions, the implant 10 can extend in an anteriordirection in a straight path directly to the anterior region in theseptum. As shown in FIG. 13, like FIG. 10A, the spanning region orbridging element 12 of the implant 10 is preformed or otherwiseconfigured to extend in an essentially straight path above the plane ofthe valve, without significant deviation in elevation toward or awayfrom the plane of the annulus, other than as dictated by the differencein elevation, if any, between the posterior and anterior regions.

Regardless of the particular location of the posterior region. (see FIG.14), the spanning region or bridging element 12 of the implant 10 can bepreformed or otherwise configured to arch upward above the plane of thevalve toward the dome of the left atrium Alternatively (see FIG. 15),the spanning region or bridging element 12 of the implant 10 can bepreformed or otherwise configured to dip downward toward the plane ofthe valve toward the annulus, extending close to the plane of the valve,but otherwise avoiding interference with the valve leaflets. Or, stillalternatively (see FIG. 16), the spanning region or bridging element 12of the implant 10 can be preformed or otherwise configured to follow acurvilinear path, bending towards a trigone (medial or lateral) of theannulus before passage to the anterior region.

Various combinations of lateral/medial deviations and superior/inferiordeviations of the spanning region or bridging element 12 of the implant10 are of course possible. For example, as shown in FIG. 17, thespanning region or bridging element 12 can follow a curvilinear pathbending around a trigone (medial or lateral) of the annulus as well aselevate in an arch away from the plane of the valve. Or, as shown inFIG. 18, the spanning region or bridging element 12 can follow acurvilinear path bending around a trigone (medial or lateral) of theannulus as well as dip toward the plane of the valve.

Regardless of the orientation, more than one implant 10 can be installedto form an implant system 22. For example, FIG. 19 shows a system 22comprising a lateral implant 10L and a medial implant 10M of a typeconsistent with the implant 10 as described. FIG. 19 shows the implants10L and 10M being located at a common anterior bridge stop region 16. Itshould be appreciated that the implants 101 and 10M can also includespaced apart anterior bridge stop regions.

One or both of the implants 10L and 10M can be straight (as in FIG. 13),or arch upward (as in FIG. 14), or bend downward (as in FIG. 15). Agiven system 10 can comprise lateral and medial implants 10L and 10M ofdifferent configurations. Also, a given system 22 can comprise more thantwo implants 10.

FIG. 20 shows a system 22 comprising two curvilinear implants 10L and10M of the type shown in FIG. 16. In FIG. 20, the curvilinear implants10L and 10M are shown to be situated at a common posterior region, butthe implants 10 can proceed from spaced apart posterior regions, aswell. One or both of the curvilinear implants 10L and 10M can beparallel with respect to the plane of the valve (as in FIG. 16), or archupward (as in FIG. 17), or bend downward (as in FIG. 18). A given system22 can comprise curvilinear implants 10L and 10M of differentconfigurations.

FIG. 21 shows a system 22 comprising a direct middle implant 10D, amedial curvilinear implant 10M, and a direct lateral implant 10L. One,two, or all of the implants 10 can be parallel to the valve, or archupward, or bend downward, as previously described.

E. Posterior and Anterior Bridge Stop

It is to be appreciated that a bridge stop as described herein,including a posterior or anterior bridge stop, describes an apparatusthat may releasably hold the bridging element 12 in a tensioned state.As can be seen in FIGS. 22A and 22B, bridge stops 20 and 18 respectivelyare shown releasably secured to the bridging element 12, allowing thebridge stop structure to move back and forth independent of theinter-atrial septum and inner wall of the great cardiac vein during aportion of the cardiac cycle when the tension force may be reduced orbecomes zero. Alternative embodiments are also described, all of whichmay provide this function. It is also to be appreciated that the generaldescriptions of posterior and anterior are non-limiting to the bridgestop function, i.e., a posterior bridge stop may be used anterior, andan anterior bridge stop may be used posterior.

When the bridge stop is in an abutting relationship to a septal memberor a T-shaped member, for example, the bridge stop allows the bridgingelement to move freely within or around the septal member or T-shapedmember, i.e., the bridging element is not connected to the septal memberor T-shaped member. In this configuration, the bridging element is heldin tension by the bridge stop, whereby the septal member or T-shapedmember serves to distribute the force applied by the bridging elementacross a larger surface area. Alternatively, the bridge stop may bemechanically connected to the septal member or T-shaped member, e.g.,when the bridge stop is positioned over and secured to the septal memberhub. In this configuration, the bridging element is fixed relative tothe septal member position and is not free to move about the septalmember.

II. General Methods of Trans-Septal Implantation

The implants 10 or implant systems 22 as just described lend themselvesto implantation in a heart valve annulus in various ways. The implants10 or implant systems 22 can be implanted, e.g., in an open heartsurgical procedure. Alternatively, the implant 10 or implant systems 22can be implanted using catheter-based technology via a peripheral venousaccess site, such as in the femoral jugular vein (via the IVC or SVC)under image guidance, or trans-arterial retrograde approaches to theleft atrium through the aorta from the femoral artery also under imageguidance.

Alternatively, the implants 10 or implant systems 22 can be implantedusing thoracoscopic means through the chest, or by means of othersurgical access through the right atrium, also under image guidance.Image guidance includes but is not limited to fluoroscopy, ultrasound,magnetic resonance, computed tomography, or combinations thereof.

The implants 10 or implant systems 22 may comprise independentcomponents that are assembled within the body to form an implant, oralternatively, independent components that are assembled exterior thebody and implanted as a whole.

FIGS. 23 to 30 show a representative embodiment of the deployment of animplant 10 of the type shown in FIGS. 10A to 10D by a percutaneous,catheter-based procedure, under image guidance.

Percutaneous vascular access is achieved by conventional methods intothe femoral or jugular vein, or a combination of both. As FIGS. 23 and24 show, under image guidance, a first catheter, or great cardiac veincatheter 40, and a second catheter, or left atrium catheter 60, aresteered through the vasculature into the right atrium. It is a functionof the great cardiac vein (GCV) catheter 40 and left atrium (LA)catheter 60 to establish the posterior bridge end stop region. Catheteraccess to the right and left atriums can be achieved through either afemoral vein to IVC or SVC route (in the latter case, for a naval brace)or an upper extremity or neck vein to SVC or IVC route (in the lattercase, for a caval brace). In the case of the SVC, the easiest access isfrom the upper extremity or neck venous system; however, the IVC canalso be accessed by passing through the SVC and right atrium. Similarlythe easiest access to the IVC is through the femoral vein; however theSVC can also be accessed by passing through the IVC and right atrium.FIGS. 23, 24, 27, 28 and 29 show access through both a SVC route and anIVC route for purposes of illustration.

The implantation of the implant 10 or implant systems 22 are firstdescribed here in four general steps. Each of these steps, and thevarious tools used, is then described with additional detail below insection III. Additionally, alternative implantation steps may be usedand are described in section IV. Additional alternative embodiments of abridge stop are described in section V, additional alternativeembodiments of a T-shaped member or bridge stop are described in sectionVI, and additional alternative embodiments of a bridging element aredescribed in section VII.

A first implantation step can be generally described as establishing theposterior bridge stop region 14. As can be seen in FIG. 24, the GCVcatheter 40 is steered through the vasculature into the right atrium.The GCV catheter 40 is then steered through the coronary sinus and intothe great cardiac vein. The second catheter, or LA catheter 60, is alsosteered through the vasculature and into the right atrium. The LAcatheter 60 then passes through the septal wall at or near the fossaovalis and enters the left atrium. A Mullins™ catheter 26 may beprovided to assist the guidance of the LA catheter 60 into the leftatrium. Once the GCV catheter 40 and the LA catheter 60 are in theirrespective positions in the great cardiac vein and left atrium, it is afunction of the GCV and LA catheters 40, 60 to configure the posteriorbridge stop region 14.

A second step can be generally described as establishing thetrans-septal bridging element 12. A deployment catheter 24 via the LAcatheter 60 is used to position a posterior bridge stop 18 and apreferably preattached and predetermined length of bridging element 12within the great cardiac vein (see FIG. 27). The predetermined length ofbridging element 12, e.g., two meters, extends from the posterior bridgestop 18, through the left atrium, through the fossa ovalis, through thevasculature, and preferably remains accessible exterior the body. Thepredetermined length of bridging element may be cut or detached in afuture step, leaving implanted the portion extending from the posteriorbridge stop 18 to the anterior bridge stop 20. Alternatively, thebridging element 20 may not be cut or detached at the anterior bridgestop 20, but instead the bridging element 20 may be allowed to extendinto the IVC for possible future retrieval.

A third step can be generally described as establishing the anteriorbridge stop region 16 (see. FIG. 29). The bridging element 12 is firstthreaded through the septal member 30. The septal member 30 is thenadvanced over the bridging element 12 in a collapsed condition throughMullins catheter 26, and is positioned and deployed at or near the fossaovalis within the right atrium. A bridge stop 20 may be attached to thebridging element 12 and advanced with the septal member 30, oralternatively, the bridge stop 20 may be advanced to the right atriumside of the septal member 30 after the septal member has been positionedor deployed.

A fourth step can be generally described as adjusting the bridgingelement 12 for proper therapeutic effects. With the posterior bridgestop region 14, bridging element 12, and anterior bridge stop region 16configured as previously described, a tension is placed on the bridgingelement 12. The implant 10 and associated regions may be allowed tosettle for a predetermined amount of time, e.g., five or more seconds.The mitral valve and mitral valve regurgitation are observed for desiredtherapeutic effects. The tension on the bridging element 12 may beadjusted or readjusted until a desired result is achieved. The bridgestop 20 is then allowed to secure the bridging element 12 when thedesired tension or measured length or degree of mitral regurgitationreduction is achieved.

III. Detailed Methods and Implantation Apparatus

The four generally described steps of implantation will now be describedin greater detail, including the various tools and apparatus used in theimplantation of the implant 10 or implant systems 22. An exemplaryembodiment will describe the methods and tools for implanting an implant10. These same or similar methods and tools may be used to implant animplant system 22 as well.

A. Establish Posterior Bridge Stop Region

1. Implantation Tools

Various tools may be used to establish the posterior bridge stop region14. For emple, the great cardiac vein (GCV) catheter 40, the left atrium(LA) catheter 60, and a cutting catheter 80 may be used.

FIG. 37A shows one embodiment of the GCV catheter 40 in accordance withthe present invention. The GCV catheter 40 preferably includes amagnetic or ferromagnetic head 42 positioned on the distal end of thecatheter shaft 45, and a hub 46 positioned on the proximal end. Thecatheter shaft 45 may include a first section 48 and a second section50. The first section 48 may be generally stiff to allow fortorquability of the shaft 45, and may be of a solid or braidedconstruction. The first section 48 includes a predetermined length,e.g., fifty centimeters, to allow positioning of the shaft 45 within thevasculature structure. The second section 50 may be generally flexibleto allow for steerability within the vasculature, i.e., into thecoronary sinus. The second section 50 may also include a predeterminedlength, e.g., ten centimeters. The inner diameter or lumen 52 of thecatheter shaft 45 is preferably sized to allow passage of a GCV guidewire 54, and additionally an LA guide wire 74 (see FIGS. 39 and 40).Both the GCV guide wire 54 and the LA guide wire 74 may be pre-bent, andboth may be steerable. The GCV catheter 40 preferably includes aradio-opaque marker 56 to facilitate adjusting the catheter under imageguidance to align with the LA catheter 60.

The magnetic or ferromagnetic head 42 is preferably polarized tomagnetically attract or couple the distal end of the LA catheter 60 (seeFIGS. 37B and 25). The head 42 includes a side hole 58 formed therein toallow for passage of the LA guide wire 74. As shown in FIG. 40, the leftatrial side 43 of the head 42 has an attracting magnetic force, and theexterior of the heart side 44 of the head 42 has a repelling magneticforce. It should be appreciated that these magnetic forces may bereversed, as long as the magnetic forces in each catheter coincide withproper magnetic attraction. The magnetic head 42 preferably includes abullet or coned shaped tip 55 to allow the catheter to track into thevasculature system. Within the tip 55 is an end hole 59, configured toallow for passage of the GCV guide wire 54.

FIG. 38 shows one embodiment of the LA catheter 60. Similar to the GCVcatheter 40, the LA catheter 60 preferably includes a magnetic orferromagnetic head 62 positioned on the distal end of the catheter shaft65 and a hub 66 positioned on the proximal end. The catheter shaft 65may include a first section 68 and a second section 70. The firstsection 68 may be generally stiff to allow for torquability of the shaft65, and may be of a solid or braided construction. The first section 68includes a predetermined length, e.g., ninety centimeters, to allowpositioning of the shaft 65 within the vasculature structure. The secondsection 70 may be generally flexible and anatomically shaped to allowfor steerability through the fossa ovalis and into the left atrium. Thesecond section 70 may also include a predetermined length, e.g., tencentimeters. The inner diameter or lumen 72 of the catheter shaft 65 ispreferably sized to allow passage of an LA guide wire 74, andadditionally may accept the guide wire 54 passed from the GCV. The LAcatheter 60 may include a radio-opaque marker 76 to facilitate adjustingthe catheter 60 under image guidance to align with the GCV catheter 40.

The magnetic or ferromagnetic head 62 of the LA catheter 60 is polarizedto magnetically attract or couple the distal end of the GCV catheter 40.As shown in FIG. 40, end side 64 of the head 62 is polarized to attractthe GCV catheter head 42. The magnetic forces in the head 62 may bereversed, as long as attracting magnetic poles in the LA catheter 60 andthe GCV catheter 40 are aligned. The magnetic head 62 preferablyincludes a generally planar tip 75, and also includes a center bore 78sized for passage of the cutting catheter 80 and the LA guide wire 74(see FIG. 38).

FIG. 41 shows the cutting catheter 80 preferably sized to be positionedwithin the inner diameter or lumen 72 of the LA catheter 60.Alternatively, the cutting catheter 80 may be positioned over the LAguide wire 74 with the LA catheter 60 removed.

The cutting catheter 80 preferably includes a hollow cutting tip 82positioned on the distal end of the catheter shaft 85, and a hub 86positioned on the proximal end. The catheter shaft 85 may include afirst section 88 and a second section 90. The first section 88 may begenerally stiff to allow for torquability of the shaft 85, and may be ofa solid or braided construction. The first section 88 includes apredetermined length, e.g ninety centimeters, to allow positioning ofthe shaft 85 within the vasculature structure and the LA catheter. Thesecond section 90 may be generally flexible to allow for steerabilitythrough the fossa ovalis and into the left atrium. The second section 90may also include a predetermined length, e.g., twenty centimeters. Theinner diameter 92 of the catheter shaft 85 is preferably sized to allowpassage of the LA guide wire 74. The cutting catheter 80 preferablyincludes a radio-opaque marker 96 positioned on the shaft 85 so as tomark the depth of cut against the radio-opaque magnet head 62 or marker76 of the LA catheter 60.

The hollow cutting or penetrating tip 82 includes a sharpened distal end98 and is preferably sized to fit through the LA catheter 60 andmagnetic head 62 (see FIG. 42A). Alternatively, as seen in FIGS. 42B and42C, cutting or penetrating tips 100 and 105 may be used in place of, orin combination with, the hollow cutting tip 82. The tri-blade 100 ofFIG. 42B includes a sharp distal tip 101 and three cutting blades 102,although any number of blades may be used. The tri-blade 100 may be usedto avoid producing cored tissue, which may be a product of the hollowcutting tip 82. The elimination of cored tissue helps to reduce thepossibility of an embolic complication. The sharp tipped guide wire 105shown in FIG. 42C may also be used. The sharp tip 106 is positioned onthe end of a guide wire to pierce the wall of the left atrium and greatcardiac vein.

2. Implantation Methods

Access to the vascular system is commonly provided through the use ofintroducers known in the art. A 16F or less hemostasis introducer sheath(not shown), for example, may be first positioned in the superior venacava (SVC), providing access for the GCV catheter 40. Alternatively, theintroducer may be positioned in the subclavian vein. A second 16F orless introducer sheath (not shown) may then be positioned in the rightfemoral vein, providing access for the LA catheter 60. Access at boththe SVC and the right femoral vein, for example, also allows theimplantation methods to utilize a loop guide wire. For instance, in aprocedure to be described later, a loop guide wire is generated byadvancing the LA guide wire 74 through the vasculature until it exitsthe body and extends external the body at both the superior vena cavasheath and femoral sheath. The LA guide wire 74 may follow anintravascular path that extends at least from the superior vena cavasheath through the interatrial septum into the left atrium and from theleft atrium through atrial tissue and through a great cardiac vein tothe femoral sheath. The loop guide wire enables the physician to bothpush and pull devices into the vasculature during the implantationprocedure (see FIGS. 35A and 36A).

An optional step may include the positioning of a catheter or catheterswithin the vascular system to provide baseline measurements. An AcuNav™intracardiac echocardiography (ICE) catheter (not shown), or similardevice, may be positioned via the right femoral artery or vein toprovide measurements such as, by way of non-limiting examples, abaseline septal-lateral. (S-L) separation distance measurement, atrialwall separation, and a mitral regurgitation measurement. Additionally,the ICE catheter may be used to evaluate aortic, tricuspid, andpulmonary valves, IVC, SVC, pulmonary veins, and left atrium access.

The GCV catheter is then deployed in the great cardiac vein adjacent aposterior annulus of the mitral valve. From the SVC, under imageguidance, the 0.035 inch GCV guide wire 54, for example, is advancedinto the coronary sinus and to the great cardiac vein. Optionally, aninjection of contrast with an angiographic catheter may be made into theleft main artery from the aorta and an image taken of the left coronarysystem to evaluate the position of vital coronary arterial structures.Additionally, an injection of contrast may be made to the great cardiacvein in order to provide an image and a measurement. If the greatcardiac vein is too small, the great cardiac vein may be dilated with a5 to 12 millimeter balloon, for example, to midway the posteriorleaflet. The GCV catheter 40 is then advanced over the GCV guide wire 54to a location in the great cardiac vein, for example near the center ofthe posterior leaflet or posterior mitral valve annulus (see FIG. 23).The desired position for the GCV catheter 40 may also be viewed asapproximately 2 to 6 centimeters from the anterior intraventricular veintakeoff. Once the GCV catheter 40 is positioned, an injection may bemade to confirm sufficient blood flow around the GCV catheter 40. Ifblood flow is low or non-existent, the GCV catheter 40 may be pulledback into the coronary sinus until needed.

The LA catheter 60 is then deployed in the left atrium. From the femoralvein, under image guidance, the 0.035 inch LA guide wire 74, forexample, is advanced into the right atrium. A 7F Mullins™ dilator with atrans-septal needle is deployed into the right atrium (not shown). Aninjection is made within the right atrium to locate the fossa ovalis onthe septal wall. The septal wall at the fossa ovalis is then puncturedwith the trans-septal needle and the guide wire 74 is advanced into theleft atrium. The trans-septal needle is then removed and the dilator isadvanced into the left atrium. An injection is made to confirm positionrelative to the left ventricle. The 7F Mullins system is removed andthen replaced with a 12F or other appropriately sized Mullins system.26. The 12F Mullins system 26 is positioned within the right atrium andextends a short distance into the left atrium.

As seen in FIG. 21, the LA catheter 60 is next advanced over the LAguide wire 74 and positioned within the left atrium. If the GCV catheter40 had been backed out to allow for blood flow, it is now advanced backinto position. The GCV catheter 40 is then grossly rotated tomagnetically align with the LA catheter 60. Referring now to FIG. 25,preferably under image guidance, the LA catheter 60 is advanced androtated if necessary until the magnetically attractant head 62 of the LAcatheter 60 magnetically attracts to the magnetically attractant head 42of the GCV catheter 40. The left atrial wall and the great cardiac veinvenous tissue separate the LA catheter 60 and the GCV catheter 40. Themagnetic attachment is preferably confirmed via imaging from severalviewing angles, if necessary.

Next, an access lumen 115 is created into the great cardiac vein (seeFIG. 26). The cutting catheter 80 is first placed over the LA guide wire74 inside of the LA catheter 60. The cutting catheter 80 and the LAguide wire 74 are advanced until resistance is felt against the wall ofthe left atrium. The LA guide wire 74 is slightly retracted, and while aforward pressure is applied to the cutting catheter 80, the cuttingcatheter 80 is rotated and/or pushed. Under image guidance, penetrationof the cutting catheter 80 into the great cardiac vein is confirmed. TheLA guide wire 74 is then advanced into the great cardiac vein andfurther into the GCV catheter 40 toward the coronary sinus, eventuallyexiting the body at the sheath in the neck. The LA catheter 60 and theGCV catheter 40 may now be removed. Both the LA guide wire 74 and theGCV guide wire 54 are now in position for the next step of establishingthe trans-septal bridging element 12.

B. Establish Trans-Septal Bridging Element

Now that the posterior bridge stop region 14 has been established, thetrans-septal bridging element 12 is positioned to extend from theposterior bridge stop region 14 in a posterior to anterior directionacross the left atrium and to the anterior bridge stop region 16.

In this exemplary embodiment of the methods of implantation, thetrans-septal bridging element 12 is implanted via a left atrium to GCVapproach. In this approach, the GCV guide wire 54 is not utilized andmay be removed. Alternatively, a GCV to left atrium approach is alsodescribed. In this approach, the GCV guide wire 54 is utilized. Thealternative GCV to left atrium approach for establishing thetrans-septal bridging element 12 will be described in detail in sectionIV.

The bridging element 12 may be composed of a suture material or sutureequivalent known in the art. Common examples may include, but are notlimited to, 1-0, 2-0, and 3-0 polyester suture, stainless steel braid(e.g., 0.022 inch diameter), and NiTi wire (e.g., 0.008 inch diameter).Alternatively, the bridging element 12 may be composed of biologicaltissue such as bovine, equine or porcine pericardium, or preservedmammalian tissue, preferably in a gluteraldehyde fixed condition.Alternatively the bridging element 12 may be encased by pericardium, orpolyester fabric or equivalent. Additional alternative bridging elementsare described in section VII.

A bridge stop, such as a T-shaped bridge stop 120 is preferablyconnected to the predetermined length of the bridging element 12. Thebridging element 12 may be secured to the T-shaped bridge stop 120through the use of a bridge stop 170 (see FIG. 44A), or may be connectedto the T-shaped bridge stop 120 by securing means 121, such as tying,welding, or gluing, or any combination thereof. As seen in FIGS. 43A and43B, the T-shaped bridge stop 120 may be symmetrically shaped orasymmetrically shaped, may be curved or straight, and preferablyincludes a flexible tube 122 having a predetermined length, e.g., threeto eight centimeters, and an inner diameter 124 sized to allow at leasta guide wire to pass through. The tube 122 is preferably braided, butmay be solid as well, and may also be coated with a polymer material.Each end 126 of the tube 122 preferably includes a radio-opaque marker128 to aid in locating and positioning the T-shaped bridge stop 120. Thetube 122 also preferably includes atraumatic ends 130 to protect thevessel walls. The T-shaped bridge stop 120 may be flexurally curved orpreshaped so as to generally conform to the curved shape of the greatcardiac vein or interatrial septum and be less traumatic to surroundingtissue. The overall shape of the T-shaped bridge stop 120 may bepredetermined and based on a number of factors, including, but notlimited to the length of the bridge stop, the material composition ofthe bridge stop, and the loading to be applied to the bridge stop.

A reinforcing center tube 132 may also be included with the T-shapedbridge stop 120. The reinforcing tube 132 may be positioned over theflexible tube 122, as shown, or, alternatively, may be positioned withinthe flexible tube 122. The reinforcing tube 132 is preferably solid, butmay be braided as well, and may be shorter in length, e.g., onecentimeter, than the flexible tube 122. The reinforcing center tube 132adds stiffness to the T-shaped bridge stop 120 and aids in preventingegress of the T-shaped member 120 through the cored or pierced lumen 115in the great cardiac vein and left atrium well

Alternative T-shaped members or bridge locks and means for connectingthe bridging element 12 to the T-shaped bridge locks are described insection VI.

As can be seen in FIG. 27, the T-shaped bridge stop 120 (connected tothe leading end of the bridging element 12) is first positioned onto orover the LA guide wire 74. The deployment catheter 24 is then positionedonto the LA guide wire 74 (which remains in position and extends intothe great cardiac vein) and is used to push the T-shaped bridge stop 120through the Mullins catheter 26 and into the right atrium, and from theright atrium through the interatrial septum into the left atrium, andfrom the left atrium through atrial tissue into a region of the greatcardiac vein adjacent the posterior mitral valve annulus. The LA guidewire 74 is then withdrawn proximal to the tip of the deployment catheter24. The deployment catheter 24 and the guide wire 74 are then withdrawnjust to the left atrium wall. The T-shaped bridge stop 120 and theattached bridging element 12 remain within the great cardiac vein. Thelength of bridging element 12 extends from the posterior T-shaped bridgestop 120, through the left atrium, through the fossa ovalis, through thevasculature, and preferably the trailing end remains accessible exteriorthe body. Preferably under image guidance, the trailing end of thebridging element 12 is gently pulled, letting the T-shaped bridge stop120 separate from the deployment catheter 24. Once separation isconfirmed, again the bridging element 12 is gently pulled to positionthe T-shaped bridge stop 120 against the venous tissue within the regionof the great cardiac vein and centered over the great cardiac veinaccess lumen 115. The deployment catheter 24 and the guide wire 74 maythen be removed (see FIG. 28).

The trans-septal bridging element 12 is now in position and extends in aposterior to anterior direction from the posterior bridge stop region14, across the left atrium, and to the anterior bridge stop region 16.The bridging element 12 preferably extends through the vasculaturestructure and extends exterior the body.

C. Establish Anterior Bridge Stop Region

Now that the trans-septal bridging element 12 is in position, theanterior bridge stop region 16 is next to be established.

In one embodiment, the proximal portion or trailing end of the bridgingelement 12 extending exterior the body is then threaded through oraround an anterior bridge stop, such as the septal member 30.Preferably, the bridging element 12 is passed through the septal member30 outside of the body nearest its center so that, when later deployedover the fossa ovalis, the bridging element 12 transmits its force to acentral point on the septal member 30, thereby reducing twisting orrocking of the septal member. The septal member is advanced over thebridging element 12 in a collapsed configuration through the Mullinscatheter 26, and is positioned within the right atrium and deployed atthe fossa ovalis and in abutment with interatrial septum tissue. Thebridging element 12 may then be held in tension by way of a bridge stop20 (see FIGS. 29 and 30). The anterior bridge stop 20 may be attached toor positioned over the bridging element 12 and advanced with the septalmember 30, or alternatively, the bridge stop 20 may be advanced over thebridging element 12 to the right atrium side of the septal member 30after the septal member has been positioned or deployed. Alternatively,the bridge stop 20 may also be positioned over the LA guide wire 74 andpushed by the deployment catheter 24 into the right atrium. Once in theright atrium, the bridge stop 20 may then be attached to or positionedover the bridging element 12, and the LA guide wire 74 and deploymentcatheter 24 may then be completely removed from the body.

FIG. 44A shows a sectional view of a bridge stop 170. The bridge stop170 is shown coupled to a catheter 172 having a bridge lock adjustmentscrew 174 at the catheter tip. In one embodiment, the bridge lockadjustment screw 174 remains coupled to the bridge stop 170 after anadjustment has been completed. In an alternative embodiment, the bridgelock adjustment screw 174 remains coupled to the catheter 172 forremoval after an adjustment has been completed. The bridge stop 170comprises a housing 176 having a lumen 178 extending axiallytherethrough. Within the lumen 178 is provided space for means forholding and adjusting the bridging element, such as clamp or law element180 and a closing spring 182. As can be seen, the clamp element 180 isin a closed position. The clamp tip(s) 184 are urged together by theforce applied to the clamp 180 by the closing spring 182. In this closedposition, the closing spring 182 exerts a predetermined force on theclamp tips 184, which in turn exert a clamping force on the bridgingelement 12 to maintain the bridging element's position. The discretestop elements 158 provide an additional barrier to maintain the bridgingelement 12 in place and to allow for adjustment of the bridging element12 to match the predefined spacing of the stop elements.

Alternatively, the catheter 172 may be used to shorten the length(increase tension) of the bridging element 12 while the clamp 180 isclosed. A catheter having a hooked tip 146 may be used to snag theexposed loop 156. The adjustment screw 174 is then screwed partiallyinto the bridge stop 170 so as to couple the catheter 172 to the bridgestop 170. While the catheter 172 is held stationary, the bridgingelement 12 is tugged to a point where the force exerted on the bridgingelement 12 and associated discrete stop elements 158 is strong enough toovercome the retentive force of the clamp 180, allowing the bridgingelement 12 and stop element 158 to pass through the clamp tips 184.

As described herein for bridge stop 170 and for alternative bridge stopsdescribed below, a relocation readjustment means (i.e., relocation loop156) may be included to provide the ability to relocate and/or readjustthe implant days, months, or even years later. This may be done afterthe initial implant procedure, or after a previous adjustment.

FIG. 44B is a sectional view of the bridge stop 170 shown in FIG. 44A,showing the bridge element adjustment feature in the open position. Ascan be seen, the adjustment screw 174 is shown threaded into the lumen178 of the bridge lock housing 176. As the adjustment screw 174 isthreaded into the bridge stop 170, the tip 186 of the adjustment screw174 exerts a force on the clamp 180 sufficient to overcome the force ofthe closing spring 182. The clamp tips 184 open to allow for bothshortening and lengthening of the bridging element 12.

The bridge stop 170, and alternative embodiments to be described later,have a predetermined size, e.g., eight millimeters by eight millimeters,allowing them to be positioned adjacent a septal member or a T-shapedmember, for example. The bridge locks are also preferably made ofstainless steel or other biocompatible metallic or polymer materialssuitable for implantation.

Additional alternative bridge stop embodiments are described in sectionV.

D. Bridging Element Adjustment

The anterior bridge stop 20 is preferably positioned in an abuttingrelationship to the septal member 30, or optionally may be positionedover the septal member hub 31. The bridge stop 20 serves to adjustablystop or hold the bridging element 12 in a tensioned state to achieveproper therapeutic effects.

With the posterior bridge stop region 14, bridging element 12, andanterior bridge stop region 16 configured as previously described, atension may be applied to the bridging element 12, either external tothe body at the proximal portion of the bridging element 12, orinternally, including within the vasculature structure and the heartstructure. After first putting tension on the bridging element 12, theimplant 10 and associated. regions may be allowed to settle for apredetermined amount of time, e.g., five seconds. The mitral valve andits associated mitral valve regurgitation are then observed for desiredtherapeutic effects. The tension on the bridging element 12 may berepeatably adjusted (as described for each bridge stop embodiment)following these steps until a desired result is achieved. The bridgestop 20 is then allowed to secure the desired tension of the bridgingelement 12. The bridging element 12 may then be cut or detached at apredetermined distance away from the bridge stop 20, e.g., zero to threecentimeters into the right atrium. The remaining length of bridgingelement 12 may then be removed from the vasculature structure.Alternatively, the bridging element 12 may include a relocation means,such as a hook or loop, or other configurations, to allow for redockingto the bridge stop sites 14, 16, for future adjustment, retrieval, orremoval of the implant system 10.

Alternatively, the bridging element 12 may be allowed to extend into theIVC and into the femoral vein, possibly extending all the way to thefemoral access point. Allowing the bridging element to extend into theIVC and into the femoral vein would allow for retrieval of the bridgingelement in the future, for example, if adjustment of the bridging'element is necessary or desired.

The bridging element adjustment procedure as just described includingthe steps of placing a tension, waiting, observing, and readjusting ifnecessary is preferred over a procedure including adjusting while at thesame time—or real-time—observing and adjusting, such as where aphysician places a tension while at the same time observes a real-timeultrasound image and continues to adjust based on the real-timeultrasound image. The waiting step is beneficial because it allows forthe heart and the implant to go through a quiescent period. Thisquiescent period allows the heart and implant to settle down and allowsthe tension forces and devices in the posterior and anterior bridge stopregions to begin to reach an equilibrium state. The desired results arebetter maintained when the heart and implant are allowed to settle priorto securing the tension compared to when the mitral valve is viewed andtension adjusted real-time with no settle time provided before securingthe tension.

FIG. 31 shows an anatomical view of mitral valve dysfunction prior tothe implantation of the implant 10. As can be seen, the two leaflets arenot coapting, and as a result the undesirable back flow of blood from,the left ventricle into the left atrium can occur. After the implant 10has been implanted as just described, the implant 10 serves to shortenthe minor axis of the annulus, thereby allowing the two leaflets tocoapt and reducing the undesirable mitral regurgitation (see FIGS. 32and 33). As can be seen, the implant 10 is positioned within the heart,including the bridging element 12 that spans the mitral valve annulus,the anterior bridge stop 20 and septal member 30 on or near the fossaovalis, and the posterior bridge stop 18 within the great cardiac vein.

IV. Alternative Implantation Steps

The steps of implantation as previously described may be altered due toany number of reasons, such as age, health, and physical size ofpatient, and desired therapeutic effects. In one alternative embodiment,the posterior T-shaped bridge stop 120 (or alternative embodiments) isimplanted via a GCV approach, instead of the left atrial approach aspreviously described. In an additional alternative embodiment, thecoring procedure of the left atrial wall is replaced with a piercingprocedure from the great cardiac vein to the left atrium.

A. GCV Approach

As previously described, penetration of the cutting catheter 80 into thegreat cardiac vein is confirmed under image guidance (see FIG. 26). Oncepenetration is confirmed, the LA guide wire 74 is advanced into thegreat cardiac vein and into the GCV catheter 40. The LA guide wire 74 isfurther advanced through the GCV catheter 40 until its end exits thebody (preferably at the superior vena cava sheath). The LA catheter 60and the GCV catheter 40 may now be removed. Both the LA guide wire 74and the GCV guide wire 54 are now in position for the next step ofestablishing the trans-septal bridging element 12 (see FIG. 35A). Atthis point, an optional exchange catheter 28 may be advanced over the LAguide wire 74, starting at either end of the guide wire 74 and enteringthe body at either the femoral sheath or superior vena cava sheath, andadvancing the exchange catheter 28 until it exits the body at the otherend of the guide wire 74. The purpose of this exchange catheter is tofacilitate passage of the LA guidewire 74 and bridging element 12, in aprocedure to be described below, without cutting or injuring thevascular and heart tissues. In a preferred embodiment, the exchangecatheter 28 is about 0.040 to 0.060 inch ID, about 0.070 to 0.090 inchOD, about 150 cm in length, has a lubricious ID surface, and has anatraumatic soft tip on at least one end so that it can be advancedthrough the vasculature without injuring tissues. It is to beappreciated that the ID, OD, and length may vary depending on thespecific procedure to be performed.

In the GCV approach, the trans-septal bridging element 12 is implantedvia a DCV to left atrium approach. A predetermined length, e.g., twometers, of bridging element 12 (having a leading end and a trailing end)is connected at the leading end to the tip of the LA guide wire 74 thathad previously exited the body at the superior vena cava sheath and thefemoral sheath. In this embodiment, the LA guide wire 74 serves as theloop guide wire, allowing the bridging element to be gently pulled orretracted into and through at least a portion of the vasculaturestructure and into a heart chamber. The vascular path of the bridgingelement may extend from the superior vena cava sheath through thecoronary sinus into a region of the great cardiac vein adjacent theposterior mitral valve annulus, and from the great cardiac vein throughatrial tissue into the left atrium, and from the left atrium into theright atrium through the interatrial septum, and from the right atriumto the femoral sheath.

As can be seen in FIGS. 34A to 34D, a crimp tube or connector 800 may beused to connect the bridging element 12 to at least one end of the LAguide wire 74. FIG. 34A shows a crimp tube 800 preferably having anouter protective shell 802 and an inner tube 804. The outer protectiveshell 802 is preferably made of a polymeric material to provideatraumatic softness to the crimp tube, although other crimpablematerials may be used. The inner tube 804 may be made of a ductile ormalleable material such as a soft metal so as to allow a crimp to holdthe bridging element 12 and guide wire 74 in place. The crimp tube ends806 may be gently curved inward to aid in the movement of the crimp tubeas the tube 800 moves through the vasculature. It is to be appreciatedthat the crimp tube may simply comprise a single tube made of a ductileor malleable material.

The bridging element 12 is positioned partially within the crimp tube800. A force is applied with a pliers or similar crimping tool to createa first crimp 808 (see FIG. 34B). The end of the bridging element mayinclude a knot, such as a single overhand knot, to aid in the retentionof the bridging element 12 within the crimp tube. Next, the LA guidewire 74 is positioned partially within the crimp tube 800 opposite thebridging element 12, A force is again applied with a pliers or similarcrimping tool to create a second crimp 810 (see. FIG. 34C).Alternatively, both the bridging element 12 and the guide wire 74 may beplaced within the crimp tube 800 at opposite ends and a single crimp 812may be used to secure both the bridging element 12 and the guide wire 74within the crimp tube (see FIG. 34D). It is to be appreciated that thecrimp tube 800 may be attached to the bridging element 12 or guide wireprior to the implantation procedure so as to eliminate the step ofcrimping the bridging element 12 within the crimp tube 800 during theimplantation procedure. The guide wire 74 is now ready to be gentlyretracted. It can also be appreciated that apparatus that uses adhesivesor alternatively pre-attached mechanisms that snap together may also beused for connecting bridge elements to guidewires.

As can be seen in FIG. 35B, the LA guide wire 74 is gently retracted,causing the bridging element 12 to follow through the vasculaturestructure. If the optional exchange catheter 28 is used (as shown inFIGS. 35A and 35B), the LA guidewire 74 retracts through the lumen ofthe exchange catheter 28 without injuring tissues. The LA guide wire 74is completely removed from the body at the femoral vein sheath, leavingthe bridging element 12 extending from eater or the body (preferably atthe femoral sheath), through the vasculature structure, and againexiting at the superior vena cava sheath. The LA guide wire 74 may thenbe removed from the bridging element 12 by cutting or detaching thebridging element 12 at or near the crimp tube 800.

A posterior bridge stop, such as a T-shaped. bridge stop 120 ispreferably connected to the trailing end of bridging element 12extending from the superior vena cava sheath. The T-shaped bridge stop120 is then positioned onto or over the GCV guide wire 54. A deploymentcatheter 24 is then positioned onto or over the GCV guide wire 54 and isused to advance or push the T-shaped bridge stop 120 and bridgingelement 12 through the right atrium, through the coronary sinus, andinto the great cardiac vein. If the optional exchange catheter 28 isused, the exchange catheter is gently retracted with the bridgingelement 12 or slightly ahead of it (see FIGS. 36A and 36B). Optionally,the bridging element 12 may be pulled from the femoral vein region,either individually, or in combination with the deployment catheter 24,to advance the T-shaped bridge stop 120 and bridging element 12 intoposition in the great cardiac vein. The GCV guide wire 54 is thenretracted letting the T-shaped bridge stop 120 separate from the GCVguide wire 54 and deployment catheter 24. Preferably under imageguidance, and once separation is confirmed, the bridging element 12 isgently pulled to position the T-shaped bridge stop 120 in abutmentagainst the venous tissue within the great cardiac vein and centeredover the GCV access lumen 115. The deployment catheter 24 and optionalexchange catheter 28 may then be removed.

The T-shaped bridge stop 120 and the attached bridging element 12 remainwithin the great cardiac vein. The length of bridging element 12 extendsfrom the posterior T-shaped bridge stop 120, through the left atrium,through the fossa ovalis, through the vasculature, and preferablyremains accessible exterior the body. The bridging element 12 is nowready for the next step of establishing the anterior bridge stop region16, as previously described, and as shown in FIGS. 28 to 30.

B. Piercing Procedure

In this alternative embodiment, the procedure to core a lumen from theleft atrium into the great cardiac vein is replaced with a procedurewhere a sharp-tipped guide wire within the great cardiac vein is used tocreate a passage from the great cardiac vein into the left atrium.Alternative embodiments for the magnetic head of both the GCV catheter40 and the LA catheter 60 are preferably used for this procedure.

FIGS. 45A and 45B show an end to side polarity embodiment for the GCVcatheter magnetic head 200 and the LA catheter magnetic head 210.Alternatively, a side to side polarity may be used. The GCV cathetermagnetic head 200 can maintain the same configuration for both the endto side polarity and the end to end polarity, while the LA cathetermagnetic head 215 is shown essentially rotated ninety degrees for theside to side polarity embodiment (See FIG. 46).

As seen in FIG. 45B, the GCV catheter magnetic head 200 includes a duallumen configuration. A navigation guide wire lumen 202 allows the GCVguide wire 54 to extend through the cone or bullet shaped end 204 of thehead 200 in order to steer the GCV catheter 40 into position. A secondradially curved side hole lumen 206 allows the sharp tipped guide wire105 (or tri-blade 100, for example) to extend through the head 200 anddirects the sharp tipped guide wire 105 into the LA catheter magnetichead 210. The LA catheter magnetic head 210 includes a funneled end 212and a guide wire lumen 214 (see FIG. 45C). The funneled end 212 directsthe sharp tipped guide wire 105 into the lumen 214 and into the LAcatheter shaft 65.

FIG. 46 shows the alternative embodiment of the LA catheter magnetichead 215 used with the side to side polarity embodiment. The head 215may have the same configuration as the GCV catheter magnetic head 42shown in FIGS. 39 and 40 and described in section III. The head 215includes a navigation guide wire lumen 216 at the cone or bullet shapedend 218, and a side hole 220. The side hole 220 funnels the sharp tippedguide wire 105 (or tri-blade 100, for example), from the GCV catheter 40to the LA catheter 60 and directs the guide wire 105 into the LAcatheter shaft 65.

In use, both the GCV catheter 40 and the LA catheter 60 are advancedinto the great cardiac vein and left atrium as previously described. TheGCV catheter 40 and the LA catheter 60 each includes the alternativemagnetically attractant head portions as just described. As best seen inFIGS. 45A and 45B, a sharp-tipped guide wire 105 is advanced through theGCV catheter 40 to the internal wall of the great cardiac vein. Thesharp-tipped guide wire 105 is further advanced until it punctures orpierces the wall of the great cardiac vein and the left atrium, andenters the funneled end 212 within the LA catheter head 210. Thesharp-tipped guide wire 105 is advanced further until it exits theproximal end of the LA catheter 60. Both the GCV catheter 40 and the LAcatheter 60 may now be removed, leaving the GCV guide wire 54 and thesharp-tipped guide wire 105 in place. The posterior T-shaped bridge stop120 is now implanted via the GCV approach, as previously described, andas shown in FIGS. 35A to 36B.

V. Alternative Bridge Stop Embodiments

Alternative embodiments of bridge stops may be used and are hereindescribed. The bridge stop may serve to secure the bridging element 12at the anterior bridge stop region 16 or the posterior bridge stopregion 14, or both. It is to be appreciated that the alternativeembodiments of the bridge stop may comprise a single element, or mayalso comprise multiple elements. In addition, the alternativeembodiments of the bridge stop may feature adjustment of the bridgingelement to tighten only, or to loosen only, or to loosen and tighten.

FIG. 47 shows a perspective view of an alternative embodiment of animplant system 10 of the type shown in FIGS. 10A to 10D. The implantsystem 10 of FIG. 47 shows the use of an exposed loop 156 allowing foradjustment or removal of the implant system, for example. As can beseen, a catheter having a hooked tip 146 may be used to snag the exposedloop 156. Radio-opaque markers 160 may be used to facilitate thegrasping or snagging of the exposed loop 156. The bridging element 12also is shown including the use of discrete stop elements 158 inconjunction with the anterior bridge stop 170.

FIG. 48 is a perspective view of an alternative embodiment of a bridgestop 390 in accordance with the present invention. The alternativebridge stop 390 preferably includes a toothed ribbon 392 and a bridgestop housing 394. The toothed ribbon 392 comprises all or a portion ofthe bridging element 12 and includes at least one row of spaced apartteeth 396 positioned along at least one edge of the ribbon. The housingincludes a locking collar 398 at one end. The locking collar 398includes a rectangular shaped opening 400 so as to allow for freemovement of the toothed ribbon 392 when the collar is in an openposition (see FIG. 48), and to engage the teeth 396 when the collar 398is in a locked position (see FIG. 49). Additional bridging element or asuture type material 402 may be coupled to the toothed ribbon 492 so asto allow the housing 494 and locking collar 398 to be positioned ontothe toothed ribbon.

In use, the bridge stop 390 allows the length of the bridging element,including the toothed ribbon 392, to be adjusted by rotating the lockingcollar 398 to the open position (see FIG. 48). A catheter (not shown) isdesirably used to grasp the locking collar 398 and to provide therotation function. Once the locking collar is in the open position, theribbon 392 may be freely moved thereby adjusting the length of thebridging element 12. Once a desired tension is established, the catheteris again used to rotate the locking collar 398 ninety degrees so as toengage the teeth 396 and hold the ribbon 392 in place (see FIG. 49).

FIG. 50 is a perspective view of an alternative embodiment of a bridgestop 410 in accordance with the present invention. The alternativebridge stop 410 preferably includes an adjusting collar or nut 414, alocking collar or nut 416, and a threaded shaft 412, the threaded shaft412 comprising all or a portion of the bridging element 12, As can beseen, both the adjusting nut 414 and the locking nut 416 may includefeatures to facilitate rotation. Adjusting nut 414 is shown with a rodor rods 418 extending radially from the nut. Locking nut 416 is shownwith one or more recesses 420 on the perimeter of the nut. Theserotation features allow a catheter to be placed over the threaded shaft412 and both the adjusting nut 414 and locking nut 416 so as to loosenthe locking nut 416, adjust the position of the adjusting nut 414,thereby adjusting the tension on the bridging element 12, and thenretighten the locking nut 416. Additional bridging element or a suturematerial 402 may be coupled to the threaded shaft 412 so as to allow theadjusting nut 414 and locking nut 416 to be positioned onto the threadedshaft.

Alternatively, a single nut 422 may be used having self locking threads,such as nylon threads (see FIG. 51). A single nut has an advantage ofreducing the number of steps necessary to adjust the bridging element12.

FIG. 52 is a perspective view of an alternative embodiment of a bridgestop 430 in accordance with the present, invention. The alternativebridge stop 430 preferably includes a perforated ribbon 432 and a bridgestop housing 434. The perforated ribbon 432 comprises all or a portionof the bridging element 12 and includes at least one row of spaced apartperforations 436 positioned along a length of the ribbon. Additionalbridging element or a suture material 402 may be coupled to theperforated ribbon 432 so as to allow the bridge stop housing 434 to bepositioned onto the perforated ribbon.

Referring to FIGS. 53 and 54, the housing includes a locking spring 438positioned within recess 440. The housing 434 may also include a tab ortabs 442 to allow coupling of adjustment catheter 444. As can be seen,the catheter 444 includes a coupling arm or arms 446 to couple to thehousing tabs 442 (see FIG. 54). This coupling between the housing andthe adjustment catheter maintains the position of the bridge stophousing 434 so as to allow the perforated ribbon 432 to be adjusted toincrease or decrease the length of the bridging element.

FIG. 53 shows the bridge stop 430 in a locked configuration. The lockingspring 438 is shown extending into a perforation 436 within the ribbon432. In order to adjust the bridging element, the catheter 444 is firstcoupled to the bridge stop housing tabs 442 by engaging the cathetercoupling arms 446. As can be seen in FIG. 54, the adjusting catheter 444is coupled to the bridge stop 430. In this adjustment configuration, theperforated. ribbon 432 is able to be pulled or pushed, causing thelocking spring 438 to temporarily flex out of the perforation 436 andinto the available recess 440. The perforations 436 may have roundededges so as to facilitate the locking spring 438 to flex out of theperforation 436 when the ribbon 432 is adjusted. The ribbon is adjustedto a point where the locking spring 438 again flexes into theperforation 436 to maintain the position of the bridging element 12.

FIGS. 55 and 56 show an alternative embodiment of a bridge stop 450 inaccordance with the present invention. The alternative bridge stop 450preferably includes a one way toothed ribbon 452 and a bridge stophousing 454 having a lumen 456 extending axially therethrough. The oneway toothed ribbon 452 comprises all or a portion of the bridgingelement 12 and includes at least one row of spaced apart teeth 458positioned along at least one edge of the ribbon. In one embodiment, theteeth 158 may be slanted to allow for one way adjustment of the ribbon452 (see FIG. 55) Within the housing lumen 456 is provided means forholding in place the one way toothed ribbon 452. As can be seen in FIGS.55 and 56, tab(s) 460 or the like are positioned within the housinglumen 456 to engage the slanted teeth 458 and allow the teeth to pass inone direction but not bi-directionally. In one embodiment, the slantedteeth 458 are generally pliable while the tabs 460 are generally rigid,so as to allow the housing to be pushed over the teeth 458 in onedirection but resist movement of the housing 454 in the oppositedirection. In an alternative embodiment, the slanted teeth 458 aregenerally rigid while the tabs 460 are generally pliable. It is to beappreciated that bridge stop 450 could also be modified to includegenerally pliable teeth 458 and tabs 460 to allow for bi-directionalmovement of the toothed ribbon 452.

FIGS. 57A through 582 show an additional alternative embodiment of abridge stop 470 in accordance with the present invention. FIGS. 57Athrough 57C show the bridge stop 470 including a bridging element 12 ina restrained configuration, while FIGS. 58A through 58C show the bridgestop 470 including a bridging element 12 in an unrestrainedconfiguration. The alternative bridge stop 470 preferably includes ahousing 472, which may be tubular in shape, although not necessary; thehousing including a top side 474, bottom side 476, inner surface 478,and outer surface 480. Within the housing is positioned a slanted wallor ramp 482 extending from at or near the top side 474 to the innersurface 478 generally at or near the bottom side 476. Positioned withinthe ramp 482 is a groove or slot 484 extending to an offset circularopening 486. The slot 484 is positioned at or near the top side 474 andextends to the circular opening 486 positioned at or near the bottomside 476.

FIGS. 57A through 57C show the bridging element 12 and associateddiscrete stop elements 158 in the restrained position. As can be seen,the slot 484 is sized so as to allow only the bridging element 12 tomove within the slot. Tension applied to the bridging element 12 in anupward direction (toward the housing top side 474) allows the ramp 482to facilitate the movement of the stop element 158 and bridging element12 into the slot 484 and to the restrained position, as shown. The stopelement 158 prevents the bridging element 12 from substantially movingin the upward direction.

FIGS. 58A through 58C show the bridging element 12 and associateddiscrete stop elements 158 in the unrestrained position. In thisconfiguration, the length (tension) of the bridging element 12 may beadjusted. As can be seen, the circular opening 486 is sized andconfigured to allow the bridging element 12, including the discrete stopelements 158, to pass through the opening 486. It is to be appreciatedthat the opening can take on any shape which associates with the shapeof the stop elements 158. Tension applied to the bridging element 12(toward the housing bottom side 476) allows the ramp 482 to facilitatethe movement of the stop element 158 and bridging element 12 down theramp 482 (i.e., out of the slot 484 and into the opening 486) and to theunrestrained position, as shown. The stop elements 158 (and bridgingelement 12) are free to pass through the circular opening 486. It is tobe appreciated that the bridging element 12 and the discrete stopelements 158 may comprise a single element, or may comprise individualstop elements coupled to the bridging element, for example.

FIGS. 59A through 60C show an alternative embodiment of the bridge stop470. The alternative bridge stop 970 preferably includes the addition ofa rotating gate 988. The rotating gate 988 provides a convenientmechanism to allow the bridging element 12 and the discrete stopelements 158 to be reset allowing for adjustment during a procedure.FIGS. 59A through 59C show the bridge stop 970 including a bridgingelement 12 in a restrained configuration, while FIGS. 60A through 60Cshow the bridge stop 970 including a bridging element 12 in anunrestrained configuration.

The alternative bridge stop 970 preferably includes a housing 972, whichmay be tubular in shape, although not necessary; the housing including atop side 974, bottom side 976, inner surface 978, and outer surface 980.Within the housing is positioned a slanted wall or ramp 982 extendingfrom at or near the top side 974 to the inner surface 978 generally ator near the bottom side 976. Positioned within the ramp 982 is a grooveor slot 984 extending to an offset circular opening 986. The slot 984 ispositioned at or near the top side 974 and extends to the circularopening 986 positioned at or near the bottom side 976.

The rotating gate 988 positioned within the housing 972 includes a slot989 sized and configured to generally match the length and width of slot984 positioned within the ramp 982. The rotating gate 988 may be hingedor otherwise rotatably coupled to the housing 972 or ramp 982. As shown,the rotating gate 988 includes pins or tabs 990 positioned withinapertures 991 to allow the gate 988 to pivot or rotate about the tabs990. The apertures 991 are positioned within the housing 972 so as toallow the rotating gate 988 to pivot or rotate at or near where the slot984 within the ramp 982 meets the offset circular opening 986. Therotating gate 988 may be held in a restrained position (as shown inFIGS. 59A through 59C) by way of a spring 994, for example, or the gatemay be allowed to move freely, its movement dependant on the tension ofthe bridging element 12 and the discrete stop elements 158. Coupled tothe outer edge 992 of the rotating gate 988 may be a reset loop 993having radio-opaque markers 160.

FIGS. 59A through 59C show the bridging element 12 and associateddiscrete stop elements 158 in the restrained position. As can be seen,the slot 984 in the ramp 982 and the slot 989 in the gate 988 are sizedso as to allow only the bridging element 12 to move within each slot.Tension applied to the bridging element 12 in an upward direction(toward the housing top side 974) allows the gate 988 to facilitate themovement of the stop element 158 and bridging element 12 into the slot988 (and slot 984) and to the restrained position, as shown. The stopelement 158 prevents the bridging element 12 from substantially movingin the upward direction.

FIGS. 60A through 60C show the bridging element 12 and associateddiscrete stop elements 158 in the unrestrained position. In thisconfiguration, the length (tension) of the bridging element 12 may beadjusted. As can be seen, the circular opening 986 is sized andconfigured to allow the bridging element 12, including the discrete stopelements 158, to pass through the opening 986. It is to be appreciatedthat the opening can take on any shape which associates with the shapeof the stop elements 158. With the aid of a catheter (not shown) thereset loop 993 is pulled in a downward direction (toward the housingbottom side 976) to urge the bridging element 12 and the discrete stopelements 158 down the rotating gate 988 (i.e., out of the slot 989) andinto the offset circular opening 986 and to the unrestrained positionfor adjustment, as shown. The stop elements 158 (and bridging element12) are free to pass through the circular opening 986. It is to beappreciated that the bridging element 12 and the discrete stop elements158 may comprise a single element, or may comprise individual stopelements coupled to the bridging element, for example.

FIG. 61 is a perspective view of an additional alternative embodiment ofa bridge stop 500 in accordance with the present invention. Thealternative slideable bridge stop 500 preferably includes a toothedribbon 502 and a bridge stop slider component 504. The toothed ribbon502 comprises all or a portion of the bridging element 12 and includesat least one row of spaced apart teeth 506 positioned along at least oneedge of the ribbon. As shown, the toothed ribbon 502 includes a row ofspaced apart teeth 506 on each side of the ribbon. The teeth 506 areshown positioned in a non-staggered saw tooth pattern. In oneembodiment, the toothed ribbon 502 has a height Hl of about 0.060inches, although the height H1 may vary. The slider component 504 maycomprise a grooved component 508 and a snap component 510.

FIGS. 62 and 63 show the grooved component 508 (FIG. 63 showing thegrooved component in section). As can be seen, the grooved component maybe generally tubular in shape and includes a lumen 512 extendingtherethrough. Positioned generally midway between a first end 514 and asecond end 516, on the outer surface 518, is a groove or channel 520extending circumjacent the outer surface 518. Positioned within thechannel 520 may be a dimple or depression 522. Desirably the channel 520may include four dimples 522 positioned ninety degrees apart from eachother. The grooved component 508 may also include a torquing pin or pins524 extending radially from the outer surface 518.

Within the lumen 512 of the grooved component 508 are positionedaxisymmetric grooves 526 (seen particularly in FIG. 63). The grooves 526may not extend completely around the inner diameter of the lumen 512. Atleast one bridging element channel 528, and desirably two parallelchannels, extends the length of the grooved component 508.

FIG. 64 shows the snap component 510 which is rotatably positionedpartially over and through the grooved component 508. The snap component510 comprises a base 530, at least one finger 532 extending from thebase 530, and a base extension 534. The base 530 and base extensioninclude a channel 536 extending therethrough. The at least one fingerdesirably comprises four fingers 532, one finger per dimple 522 on thegrooved component 508. At the tip of each finger 532 may be positioned atab 538 that works in cooperation with dimples 522 to act as a detent torestrict rotational movement of the snap component 510 about the groovedcomponent 508.

In use, the snap component 510 is positioned over the grooved component508, as can be seen in FIG. 61. The toothed ribbon 502 is allowed to beadjusted (lengthening or shortening of the bridging element) when thechannel 528 in the grooved component 508 lines up with the channel 536in the snap component. In this adjustment configuration (see FIG. 65),the spaced apart teeth 506 on the toothed ribbon 502 are not restrainedby the grooves 526 positioned with the grooved component 508, and theribbon 502 is free to slide within the bridge stop 500. The detentfeature (dimples 522 and tabs 538) provide predefined adjustment andrestrained positions for the bridge stop 500 to more simply convertbetween the adjustment configuration and the restrained configuration.

When a desired tension is achieved on the bridging element 12, acatheter having a torquing tool 540 (see FIG. 67) on its distal end isused to rotate the grooved component 508 in either a clockwise orcounter-clockwise direction while maintaining the position of thetoothed ribbon (and snap component 510) so as to engage the spaced apartteeth 306 within the matching grooves 526 of the grooved component 508,thereby restraining the toothed ribbon 502 (see FIG. 66). Again, thedetent feature (dimples 522 and tabs 538) provides a predefinedrestrained position to maintain the bridge stop 500 in this restrainedconfiguration after the torquing tool 540 has been removed.

As can be seen in FIG. 67, the torquing tool 540 may comprise an outertorquer 542 and an inner torquer 544. The outer torquer 542 includes atleast one recess 546 at its distal end 548 to engage the torquing pin orpins 524 on the grooved component 508. The inner torquer 544 (positionedwithin the outer torquer 542) includes a channel 550 sized andconfigured to allow the toothed ribbon to extend within the innertorquer 544.

In an alternative embodiment of the slideable bridge stop 500, the screwthreaded bridge stop 560 (see FIG. 68) preferably includes a toothedribbon 562 and a bridge stop screw threaded component 564. The toothedribbon 562 comprises all or a portion of the bridging element 12 andincludes at least one row of spaced apart teeth 566 positioned along atleast one edge of the ribbon. As shown, the toothed ribbon 562 includesa row of spaced apart teeth 566 on each side of the ribbon. The teeth566 are shown positioned in a staggered saw tooth pattern. In oneembodiment, the toothed ribbon 562 has a height H2 of about 0.060inches, although the height H2 tray vary. The screw threaded component564 may comprise a threaded component 568 and a base component 570.

FIGS. 69 and 70 show the threaded component 568 (FIG. 70 showing thethreaded component in section). As can be seen, the threaded componentmay be generally tubular in shape and includes a lumen 572 extendingtherethrough. Positioned generally midway between a first end 574 and asecond end 576, on the outer surface 578, is a groove or channel 580extending circumjacent the outer surface 578. The threaded component 568may also include a pin or pins 584 extending radially from the outersurface 578.

Within the lumen 572 of the threaded component 578 are positionedhelical (threaded) grooves 586 (seen particularly in FIG. 70). Thegrooves 586 extend completely around the inner diameter of the lumen572,

FIG. 71 shows the base component 570 which is rotatably positionedpartially over and through the threaded component 568. The basecomponent 570 comprises a base or hub 590 and a base extension 594. Thehub 590 and base extension 594 include a channel 596 extendingtherethrough. One or more bores 598 are positioned within the hub 590and are sized and configured to restrain a pin 600. Two bores 598 areshown in FIG. 71. After the threaded component 568 is coupled to thebase component 570, the pins 600 are inserted into the bores 598. Thebores 598 are positioned to allow the inserted pins 600 to be positionedwithin the channel 580 on the threaded component 568. The pins 600retain the base component 570 on the threaded component 568 yet allowfor rotation of the threaded component 568 relative to the basecomponent 570.

In use, the base component 570 is positioned over the grooved component568, as can be seen in FIG. 68. When the bridging element 12 is to beadjusted, a catheter having a torquing tool 540 (as can be seen in FIG.67 and described above) on its distal end is used to rotate the threadedcomponent 568 in either a clockwise or counter-clockwise direction. Thehelical grooves 586 of the threaded component 568 engage the teeth 566of the toothed ribbon 562, causing the toothed ribbon to thread throughthe bridge stop 560, which in turn lengthens or shortens the toothedribbon 562 (bridging element). When a desired tension of the bridgingelement is achieved, the torquing tool 540 is removed.

It is to be appreciated that each embodiment of the bridge stop may beconfigured to have a bridge securing configuration in a static state, soas to require a positive actuation force necessary to allow the bridgingelement to move freely within or around the bridge stop. When adesirable tension in the bridge element is achieved, the actuation forcemay be removed, thereby returning the bridge stop back to its staticstate and securing the bridge stop to the bridging element.Alternatively, the bridge stop may be configured to allow free movementof the bridging element 12 in its static state, thereby requiring apositive securing force to be maintained on the bridge stop necessary tosecure the bridging element within the bridge stop.

Preferably, the bridge securing feature is unambiguous via tactile orfluoroscopic feedback. The securing function preferably may be lockedand unlocked several times, thereby allowing the bridging element to bereadjusted. The bridge stop material is also desirably radio-opaque orincorporates radio-opaque features to enable the bridge stop to belocated with fluoroscopy.

As previously described, the bridging element 12 may comprise a singleelement, or may also comprise multiple elements. In numerous embodimentsdescribed above, the bridging element comprised multiple elements. FIG.72 shows an example where the toothed ribbon 502 of the bridge stop 500comprises a portion of the bridging element 12. As can be seen, thetoothed ribbon 502, for example, extends through the bridge stop 500 andthrough a septal member 30, and is then coupled to a segment of bridgingelement 12. The toothed ribbon 502 may be coupled to the bridgingelement 12 by way of tying, gluing, crimping, welding, or machined froma single piece of material, as non-limiting examples.

In an alternative embodiment, the toothed ribbon 502, for example, maycomprise the entire bridging element, as shown in FIG. 73. As can beseen, the toothed ribbon 502 extends through the bridge stop 500 andthrough a septal member 30, and continues through the left atrium to theposterior bridge stop region 14, where it is coupled to the posteriorbridge stop 18.

A segment of bridging element 12 may also extend into the right atriumas shown in FIG. 72 to allow for retrieval of the implant system oradjustment of the bridging element. As can be seen, a segment ofbridging element comprising an exposed loop 156 extends from the toothedribbon 502. Radio-opaque markers 160 may be used to facilitate thegrasping or snagging of the exposed loop 156.

In an alternative embodiment, the toothed ribbon 502 may comprise an inintegral hook or loop 303 to allow for retrieval of the implant systemor adjustment of the bridging element. Radio-opaque markers 160 may beused to facilitate the grasping or snagging of the exposed loop 303.

VI. Alternative T-shaped Bridge Stop Embodiments

Alternative embodiments of T-shaped bridge stops may be used and areherein described. The T-shaped bridge stop may serve to secure thebridging element 12 (or alternative bridging element embodiments) at theanterior bridge stop region 16 or the posterior bridge stop region 14,or both. It is to be appreciated that the alternative embodiments of theT-shaped bridge stop may comprise a single element, or may also comprisemultiple elements, as shown and described in FIG. 43A and 43B, forexample. It is also to be appreciated that the alternative embodimentsof the T-shaped bridge stop devices may be symmetrical, or may also beasymmetrically shaped. In addition, the alternative embodiments of theT-shaped bridge stop may feature adjustment of the bridging element totighten only, or to loosen and tighten.

FIG. 74 is a perspective view of an alternative embodiment of a T-shapedbridge stop 680 in accordance with the present invention. Thealternative T-shaped bridge stop 680 preferably includes an externallythreaded male member 682 nested partially within an internally threadedfemale member 684. The male member 682 includes a tubular portion 686extending from the end 688 that is positioned within the female memberto about the middle of the male member 682, although the tubular portion686 may extend past the middle of the male member, including extendingthe full length of the male member 682, or may extend less than to themiddle of the male member. An aperture 690 is positioned in the malemember 682 and extends from the outside surface 692 of the male memberto the tubular portion 686.

In use, the T-shaped bridge stop 680 allows the length of the bridgingelement 12 to be adjusted by rotating the female member in either aclockwise or counterclockwise direction. As can be seen in FIG. 74, acatheter 694 may be used to couple to the end 696 of the female member684 to provide rotation of the female member. Bridging element 12 isfixed at 698 within the female member 684, such that rotation of thefemale member 684 causes the overall length of the T-shaped bridge stop680 to expand or contract, thereby adjusting the length of the bridgingelement 12. The T-shaped bridge stop 680 is shown positioned within thelumen of a vessel 700. The bridging element 12 extends from fixationpoint 698 through the tubular portion 686 of the male member, thenthrough the aperture 690, and through the vessel wall at 702. Thepenetration of the bridging element 12 through the vessel wall at 702and through aperture 690 stops the male portion 682 from rotating,thereby allowing rotation of the female member 684 to adjust the lengthof the bridging element 12.

FIG. 75 is a perspective view of an alternative embodiment of a T-shapedbridge stop 710 in accordance with the present invention. Thealternative T-shaped bridge stop 710 preferably includes a ratchetingmechanism 712 having a first member 720 and a second member 722 (e.g.,ball point pen style mechanism), and a compression spring 714 working incooperation with the ratcheting mechanism 712, both of which may bepositioned within a tubular member 716. An aperture 718 is positionedgenerally midway the tubular member 716 (although other positions alongthe length of the bridge stop are possible) that allows the bridgingelement 12 to pass through the wall of the tubular member 716 and coupleto the ratcheting mechanism 712.

In use, the T-shaped bridge stop 710 allows the length of the bridgingelement 12 to be adjusted by operation of the ratcheting mechanism 712.As can be seen in FIG. 75, a catheter 694 may be used to couple to thefirst member 720 of the ratcheting mechanism 712 to provide an axialforce to the ratcheting mechanism, which in turn rotates the secondmember 722 of the ratcheting mechanism. Discrete segments of thebridging element 12 are allowed to be dispensed or retracted throughaperture 718 when the first end 720 is pushed with the catheter 694. Thecatheter 694 may also release and reset any tension on the bridgingelement 12 by rotating the ratcheting mechanism 712. Rotation of thesecond member 722 causes the bridging element 12 to wrap around thesecond member 722, thereby adjusting the length of the bridging element12. As shown in FIG. 74, the T-shaped bridge stop 710 may be positionedwithin a vessel or against an organ wall. The penetration of thebridging element 12 through the vessel wall and through aperture 718stop the tubular member 716 from rotating, thereby allowing rotation ofthe second member 722 to adjust the length of the bridging element 12.

FIG. 76 is a perspective view of an alternative embodiment of a T-shapedbridge stop 730 in accordance with the present invention. Thealternative T-shaped bridge stop 730 preferably includes a tubularmember 732 having an aperture 734, and a clamp 736 positioned within thetubular member 732. The aperture 734 is positioned generally midway thetubular member 732 (although other positions along the length of thebridge stop are possible) and the clamp 736 is positioned generally neara first end 738 of the tubular member. Within the tubular member 732,generally near the second end 740, the bridging element is coupled tothe tubular member at fixation point 742.

In use, the T-shaped bridge stop 730 allows the length of the bridgingelement 12 to be shortened (increase in tension) by pulling on theexposed loop 744 of the bridging element 12 with a catheter having meansfor adjustment, such as a hooked tip 746. It is to be appreciated thatadditional means to couple to the exposed end of the bridging element 12are contemplated as well, such as a clamp, loop, or magnetics, forexample. As can be seen in FIG. 76, the catheter 746 is used to snag andthen pull on the exposed loop 744. By pulling on the exposed loop, oneleg of the bridging element 12 is pulled through the clamp 736. Thepulling force must be greater than the clamping force of the clamp 736so as to maintain the position of the bridging element within the clampwhen the exposed loop 744 is released. The clamp 736 may includeserrated jaws 748 to improve the ability of the clamp 736 to allow thebridging element 12 to be pulled through it for increasing tension, yetnot allow the tension on the bridging element 12 to pull the bridgingelement back through the clamp 736 (which would cause a decrease intension).

FIG. 77 is a perspective view of an alternative embodiment of a T-shapedbridge stop 750 in accordance with the present invention. Thealternative T-shaped bridge stop 750 preferably includes a tubularmember 752 having a slit 754. The slit 754 is positioned generallymidway the tubular member 752, although other positions along the lengthof the bridge stop are possible.

In use, the T-shaped bridge stop 750 allows the length of the bridgingelement 12 to be shortened (increase in tension) by pulling on theexposed loop 756 of the bridging element 12 with an adjustment catheterhaving a hooked tip 146, for example. As can be seen in FIG. 77, in thisembodiment, the bridging element 12 includes discrete bead or stopelements 158. The catheter 146 is used to snag and then pull on theexposed loop 156. By pulling on the exposed loop, the bridging element12, including the discrete stop elements 158, is pulled through the slit754. The slit 754 allows the beads to be pulled into the tubular member752, but not out of the tubular member. The slit 754 may include flaps760 (e.g., as in a duck bill valve) to help maintain the tension on thebridging element 12 and to keep the discrete stop elements 158 frombeing pulled out of the tubular member 752 by the tension on thebridging element 12. The discrete stop elements 158 may be positionedapart from each other at predefined lengths (e. g., about 2 mm to about5 mm), so as to allow shortening of the bridging element at thesepredefined lengths.

VII. Alternative Bridging Element Embodiments

Alternative embodiments of bridging elements may be used and are hereindescribed. The bridging element may serve to secure the anterior bridgestop region 16 to the posterior bridge stop region 14. It is to beappreciated that the alternative embodiments of the bridging element maycomprise a single element, or may also comprise multiple elements.

FIG. 78 is a perspective view of an alternative embodiment of an implantsystem 10 having a bridging element 770 in accordance with the presentinvention. The bridging element 770 having a first end 772 and a secondend 774 is shown extending through a septal member 30 and coupled to aposterior bridge stop 18. The bridging element may also couple to theseptal member 30. Bridging element 770 desirably comprises a ribbon ofmaterial having ductile properties (i.e., capable of being shaped, bent,or drawn out), such as stainless steel. By twisting the bridging element770, which may be accomplished at the posterior bridge stop region 14and/or the anterior bridge stop region 16, the bridging element shortensor lengthens, and because the bridging element yields, it stays at thedesired length. The twisting force necessary to adjust the bridgingelement 770 is greater than the tension force on the bridging element.The twisting may be accomplishes with an adjustment catheter (notshown).

FIG. 79 is a perspective view of an additional alternative embodiment ofan implant system 10 having a bridging element 780 in accordance withthe present invention. The bridging element 780 is shown extendingthrough a septal member 30 and coupled to a posterior bridge stop 18.The bridging element may also couple to the septal member 30. Bridgingelement 780 desirably comprises at least one loop of bridging element.The first end 782 of bridging element 780 may be coupled to the septalmember 30, or alternatively coupled to the anterior bridge stop 20, oralternatively, coupled to the grommet 32. From the first end 782, thebridging element loops around a hook or retainer 784 coupled to theposterior bridge stop 18 and then extends back to and through the septalmember 30. The looped bridging element 780 doubles the length of thebridging element, and in doing so allows for a finer adjustment of theimplant system 10 because of the improved pulling ratio of ½ unit to 1unit.

FIG. 80A is a perspective view of an additional alternative embodimentof an implant system 10 having a bridging element 790 in accordance withthe present invention. The bridging element 790 having a first end 792and a second end 794 is shown having an integral anterior bridge stop 26and also coupled to a posterior bridge stop 18. It is to be appreciatedthat the bridging element 790 may have an integral posterior bridgestop, or may have both an integral anterior and posterior bridge stop aswell. Bridging element 790 desirably comprises braided Nitinol wireshaving a predefined length. The braided Nitinol wires are desirably leftstraight for a predefined range (e.g., about 8 cm to about 10 cm). Apredefined portion of the braided Nitinol wires (e.g., about 1 cm toabout 3 cm), are pre-shaped to curl into an anterior bridge stop 796when released from a delivery catheter in the right atrium. FIGS. 80Band 80C show varying configurations of the first end 792 (i.e., theanterior bridge stop 796), as tension on the bridging element 790increases (see FIG. 80B) or decreases (see FIG. 80C).

The foregoing is considered as illustrative only of the principles ofthe invention. Furthermore, since numerous modifications and changeswill readily occur to those skilled in the art, it is not desired tolimit the invention to the exact construction and operation shown anddescribed. While the preferred embodiment has been described, thedetails may be changed without departing from the invention, which isdefined by the claims.

1. A bridge stop apparatus comprising a bridge stop housing having alength and a width, an aperture extending through the length of thebridge stop housing, the aperture sized and configured to allow abridging element to extend through at least a portion of the length ofthe aperture, and an adjustment mechanism coupled to the bridge stophousing to allow adjustment of a length of the bridging element.
 2. Abridge stop according to claim 1 wherein the adjustment mechanismincludes a catheter releasably coupled to the bridge stop to activatethe adjustment mechanism.
 3. A bridge stop according to claim 1 whereinthe adjustment mechanism is located within the aperture within thebridge stop housing.
 4. A bridge stop according to claim 1 wherein theadjustment mechanism comprises a locking collar.
 5. A bridge stopaccording to claim 1 wherein the adjustment mechanism allows for onlylengthening or only shortening of the bridging element. 6.-14.(canceled)
 15. A bridge stop apparatus comprising a bridge stop housing,the housing comprising an inner portion and an outer portion, thehousing having a length and a width, an aperture extending through thelength of the bridge stop housing, the aperture sized and configured toallow a bridging element to extend through at least a portion of thelength of the aperture, and an adjustment mechanism coupled to thebridge stop housing to allow adjustment of the bridging element.
 16. Abridge stop according to claim 15 wherein the adjustment mechanismcomprises rotation of either the inner portion or the outer portion. 17.A bridge stop according to claim 15 wherein the inner portion ispositioned completely within the outer portion.
 18. A bridge stopaccording to claim 15 wherein the inner portion extends partiallyoutside the outer portion.
 19. An implant system comprising a bridgingelement sized and configured to span a left atrium between a greatcardiac vein and an interatrial septum, a first bridge stop coupled tothe bridging element, a second bridge stop coupled to the bridgingelement, the second bridge stop comprising, a bridge stop housing havinga length and a width, an aperture extending through the length of thebridge stop housing, the aperture sized and configured to allow abridging element to extend through at least a portion of the length ofthe aperture, and an adjustment mechanism coupled to the bridge stophousing to allow adjustment of the bridging element.
 20. An implantsystem according to claim 19 wherein the bridge stop housing furthercomprises an inner portion and an outer portion.
 21. An implant systemaccording to claim 20 wherein the adjustment mechanism comprisesrotation of either the inner portion or the outer portion to allow thebridging element to be lengthened or shortened.
 22. A method ofadjusting a bride stop as defined in claim
 1. 23. A method of adjustinga length of a bridging element comprising providing a bridge stop havingan adjustment mechanism as defined in claim 1, and operating theadjustment mechanism to lengthen or to shorten the bridging element. 24.A method according to claim 23 further including repeating the operatingthe adjustment mechanism to lengthen or shorten the bridging elementuntil a desired length of the bridging element is achieved.
 25. A methodaccording to claim 24 further including allowing the bridging element tosettle for a predetermined time before repeating the operating theadjustment mechanism step.
 26. A method according to claim 23 furtherincluding coupling a catheter to the bridge stop, the catheter beingused to operate the adjustment mechanism.
 27. A method according toclaim 23 further including coupling a catheter to the bridging element,the catheter being used to lengthen or shorten the bridging element. 28.A method according to claim 23 further including providing a catheter,the catheter including a proximal end and a distal end, the catheterhaving a first adjustment mechanism on its proximal end and a secondadjustment mechanism on its proximal end, coupling the first adjustmentmechanism to the bridge stop, coupling the second adjustment mechanismto the bridging element, operating the first adjustment mechanism toallow adjustment of the bridging element, operating the secondadjustment mechanism to lengthen or shorten the bridging element, andoperating the first adjustment mechanism again to re-secure the bridgingelement.